Question

a-b=0.9
ab = 0.36
find a+b and a²-b²

Answer 1

use below :
\(\large (a+b)^2 = (a-b)^2 + 4ab\)

\(\large a^2-b^2 = (a+b)(a-b)\)

Answer 2

so is a² + b² = 1.53?????

Answer 3

why do we need \(a^2 + b^2\) ?

Answer 4

idk weak at this

Answer 5

we can find the value of \((a+b)^2\) and take square root to get the value of \(a+b\)

Answer 6

?

Answer 7

a-b=0.9
ab = 0.36


\(\large (a+b)^2 = (a-b)^2 + 4ab = (0.9)^2 + 4(0.36) = ?\)

Answer 8

its not 4ab its 2ab

Answer 9

in my country

Answer 10

haha thats hilarious, whats your country ? :)

Answer 11

like
(a-b)² = a² + b² - 2ab

Answer 12

yes, add 4ab to that identity and see what you get ^

Answer 13

??
do and show using 2ab and not 4ab

Answer 14

(a-b)² + 4ab = a² + b² - 2ab + 4ab
= ?

Answer 15

pl this 4ab is confusing me

Answer 16

usein the one i yold

Answer 17

use tthe one i told

Answer 18

Alright, are these your formulas :

\((a+b)^2 = a^2 + b^2 + 2ab\)
\((a-b)^2 = a^2 + b^2 - 2ab\)

?

Answer 19

yep

Answer 20

subtract them and tell me what you get

Answer 21

(0.9)² = a² + b² - 2 x 0/36

Answer 22

that looks good ^

Answer 23

its .36 not 36

Answer 24

so now

Answer 25

find the value of \(a^2 + b^2\)

Answer 26

1.53????

Answer 27

Correct !

Answer 28

\((a+b)^2 = a^2 + b^2 + 2ab\)

Answer 29

?

Answer 30

plugin the values, then take squareroot

Answer 31

so now what i do

Answer 32

i alwyas get stuck here

Answer 33

\((a+b)^2 = 1.53 + 2(0.36)\)

Answer 34

.81??????

Answer 35

try again

Answer 36

tried 8 times

Answer 37

...

Answer 38

\((a+b)^2 = 1.53 + 2(0.36) = 2.25\)

\(\implies a+b = \pm 1.5\)

Answer 39

ok now

Answer 40

a²-b²

Answer 41

Notice that you got two values for \(a+b\) : -1.5, +1.5

Answer 42

for calculating \(a^2-b^2\), use the identity : \(a^2 - b^2 = (a+b)(a-b)\)

Answer 43

when a+b = -1.5 :

\(a^2 - b^2 = (-1.5)(0.9) = ?\)

Answer 44

idk

Answer 45

just multiply -1.5 and 0.9

Answer 46

use ur calculator

Answer 47

more questions

Answer 48

yea sure

Answer 49

a-b = 4
a+b = 6
find a² + b² n ab

Answer 50

is ab = 5?

Answer 51

you're given system of equations,
solve \(a\) and \(b\)

Answer 52

is ab = 5?

Answer 53

Yep !

Answer 54

n the last part 26?

Answer 55

Correct ! good job :)

Answer 56

more questions

Answer 57

okay

Answer 58

3x + 4y = 16
xy = 4
find the value of 9x² + 16x²

Answer 59

@ganeshie8

Answer 60

@ganeshie8

Answer 61

@skullpatrol

Answer 62

3x + 4y = 16


square both sides

Answer 63

(3x + 4y)^2 = 16^2

Answer 64

expand

Answer 65

(3x + 4y)^2 = 16^2


(3x)^2 + (4y)^2 + 2(3x)(4y) = 256

9x^2 + 16y^2 + 24xy = 256

Answer 66

plugin the value of xy

Answer 67

thtas it?

Answer 68

yes thats it

Answer 69

ty

Answer 70

you're given xy = 4 :

9x^2 + 16y^2 + 24xy = 256

9x^2 + 16y^2 + 24(4) = 256

9x^2 + 16y^2 = 256 - 24(4)

Answer 71

simplify^