Question

f(7)= -x2+3x-6

i got 64 but its says its wrong

Answer 1

\[f(x)=-x^2+3x-6 \\ \text{ and you are asked to evaluate } f(7) ?\]

Answer 2

by the way -x^2 means -1*x*x

Answer 3

-x^2 is not the same as (-x)^2

Answer 4

which looks like what you did

Answer 5

oh it does 0_0

i put

-7^2+3(7)-6

Answer 6

which is -49+21-6

Answer 7

wait for mines i got

49+21-6 = 64

Answer 8

as said you did (-x)^2

Answer 9

but the question says -x^2

Answer 10

-x^2 is -1*x*x
not (-x)*(-x)

Answer 11

\[-x^2=-1 \cdot x^2 \text{ or } -1 \cdot x \cdot x \\ \text{ where as } (-x)^2 =(-x) \cdot (-x)=x \cdot x =x^2 \text{ which is what you did } \\ \text{ and } -x^2 \text{ does not equal } (-x)^2 \]

Answer 12

so can u give it to me when you first plug it in

Answer 13

so its

-7^2 ?

Answer 14

yes not (-7)^2

Answer 15

the exponent is on the x not the - and the x

Answer 16

\[g(x)=-x^2 \\ g(7)=-7^2=-(7^2)=-(7 \cdot 7)=-(49)=-49\]

Answer 17

so thats -49?

Answer 18

if you had
\[h(x)=(-x)^2 \\ \text{ then } h(7)=(-7)^2=(-7 \cdot -7)=49\]

Answer 19

OHOHOHOHHOHO i seeeeeee

Answer 20

so if its for example f(8)

we put

-8^2 so 8*8=64 and the negative sign is after so -64

Answer 21

yes -8^2 means -(8*8)=-(64)=-64

Answer 22

where as (-8)^2=(-8)*(-8)=64

Answer 23

so the answer is *34?

Answer 24

do you see difference between -x^2 and (-x)^2 ?

Answer 25

-34?

Answer 26

\[-7^2+3(7)-6 \\ -49+21-6 \\ -(49-21)-6 \\ -(28)-6 \\ -28-6 \\ -34\]
yes

Answer 27

OMG your the best thanks!!!!!

Answer 28

np