Question

Evaluate the expression below when x = -1.

2x2 − 5

x + 9

Answer 1

somebody help me please

Answer 2

please help me and sheppard18 these questions is what we are depending on to graduate

Answer 3

??

Answer 4

??

Answer 5

hello??

Answer 6

replace x by -1

Answer 7

is that the answer

Answer 8

nope

Answer 9

whats the answer

Answer 10

Just substitute it.

Answer 11

\[2(-1)^2 -5\]
substitute value and then solve !

Answer 12

i dont know how to substitute because we have never ever had a half decent math teacher

Answer 13

\(\color{blue}{\text{Originally Posted by}}\) @Nnesha
\[2(-1)^2 -5\]
substitute value and then solve !
\(\color{blue}{\text{End of Quote}}\)
like this just replace x and plug -1 now solve
what is square of (-1) ?

Answer 14

(-1)^2 is same as -1 times -1 = what ?

Answer 15

i dont know what the answer is

Answer 16

For example x=12.
3(x)+2=y
3(12)+2=y <---------------------------------
36+2=y |
38=y |
|
See how I substituted x as 12 to solve the example equation? -------

Answer 17

what is -1 times -1 = ??

Answer 18

Arrow line messed up.

Answer 19

-1?

Answer 20

negative times negative = positive
negative times positive = negative
so negative 1 times negative 1 = ?

Answer 21

@sheppard18 what do you think ?
-1 times -1 = ??

Answer 22

1?

Answer 23

yes right

Answer 24

1 is not a choice

Answer 25

\[2(-1)^2 -5\]
\[2(1)-5 =what ??\]

Answer 26

i didn't say one is the answer

Answer 27

-7/8, -3/8, -1/8, -1 theses are the choices we have

Answer 28

-3?

Answer 29

Example:
x+2=y
You know that x is 1 but you need to find out y.
So you put \(\color{red}{x~as~1}\) in the equation.
\(\color{red}{(1)}\)+2=y.
1+2=3 so y=3.

Get it?

Answer 30

yes that's right!
remember PEMDAs rule
Parentheses
exponent
MD) MULTIPLY OR DIVIDE
AS ) ADD OR SUBTRACT

Answer 31

please just tell me the answer

Answer 32

were from tug valley we dont know much

Answer 33

you have to learn in order to know something

Answer 34

are teacher does nothing but sleep in class

Answer 35

and calls the office on our class because our class is so mean

Answer 36

alright thanks for joining os
here we will teach u
no direct answers!!

Answer 37

well how do i do it

Answer 38

\(\color{blue}{\text{Originally Posted by}}\) @estepp33
-3?
\(\color{blue}{\text{End of Quote}}\)
yes right

Answer 39

what about -3

Answer 40

substitute given x value which is -1 \[\huge\rm 2(-1)^2 -5 \]

take square of -1 which is 1 (-1 times -1 = 1)
\[2(1)-5 = ???\]

Answer 41

that comes out to be -3 what do we do with the -3

Answer 42

that's the answer of first one

Answer 43

i guess your question is \[\frac{ 2x^2 -5 }{ x+9 }\]
right it's a fraction ?

Answer 44

it will be a fraction or a whole numbner

Answer 45

yes its a fraction i need help with the bottom now

Answer 46

so why you didn't tell me ??
use */* for fraction so we know it's a fraction

Answer 47

i thought those are 2 different expression

Answer 48

\[\huge\rm \frac{ 2\color{blue}{x^2} -5 }{ \color{blue}{x}+9 }\]
just like we did before
replace x by -1

Answer 49

would the answer be -3/8

Answer 50

that's right

Answer 51

i got 8

Answer 52

yes the denominator is 8

Answer 53

can u help me with this question

The simplest form of the expression 4m−17m2−16+3m−11m2−16 has in the numerator and in the denominator.

Answer 54

and how do i know what is in the numerator and what is in the denominator
use the equation and type ur question

Answer 55

i dont know

Answer 56

what ?

Answer 57

\[\huge\rm 4m−17m^2−16+3m−11m^2−16\]
like this ?

Answer 58

4m-17/m^2-16+3m-11/m^2-16

Answer 59

that is the fraction ^

Answer 60

4m-17/m^2 this is the fraction

Answer 61

\[\huge\rm \frac{ 4m-17 }{ m^2 } -\frac{ 16+3m-11 }{ m^2 -16 }\] like this ?

Answer 62

yea

Answer 63

m^2-16 on both bottom sides

Answer 64

\[\huge\rm \frac{ 4m-17 }{ m^2 -16} -\frac{ 16+3m-11 }{ m^2 -16 }\]
looks good ?

Answer 65

yes

Answer 66

no

Answer 67

alright type your question please

Answer 68

4m-17/m^2-16 + 3m-11/m^2-16

Answer 69

the minus sign should be plus and the 16 on top on the right shouldnt be there

Answer 70

\[\huge\rm \frac{ 4m-17 }{ m^2 -16} +\frac{ 3m-11 }{ m^2 -16 }\]
find common denominator?
what is common denominator ?

Answer 71

16

Answer 72

16?

Answer 73

??

Answer 74

1not just 16
m^2 -16 should be together \[\huge\rm \frac{ }{m^2 -16 }\]
so m^2 and -16= common denominator

Answer 75

ok what do i do

Answer 76

now bec denominator of both fraction are same as common denominator so just carry down the value of numerator \[\huge\rm \frac{ 4m-17+3m-11 }{ m^2 -16 }\]
now combine like terms
4m-17+3m -11= what ?

Answer 77

-21

Answer 78

how did yo uget -21 ?

Answer 79

i done 4-17+3-11

Answer 80

what are LIKe terms ?

Answer 81

you can't combine 4m with -17 bec there are not the same

Answer 82

3 and 4

Answer 83

add coefficient of same variable
yes right 3m and 4m combine them

Answer 84

3m+4m =what ?
-17-11= ?

Answer 85

7 and -28

Answer 86

??

Answer 87

\[ \huge\rm \frac{ 7m -28 }{ m^2 -16 }\]
now factor 7m-28 what is common factor ?

Answer 88

nd apply difference of square for the denominator part \[\rm a^2 - b^2 = (a+b)(a-b)\]

Answer 89

what do i do with that

Answer 90

alright first factor the numerator
7m-28 what is common factor ?

Answer 91

is it m+4

Answer 92

??

Answer 93

for which one ?

Answer 94

the right one

Answer 95

alright 7m-28 what is common in these both terms ??

Answer 96

i got to go im going home

Answer 97

thanks for the help