Please help! I will mark as brainliest IF answer is right. <3

For f(5x) we replace x by 5x in function ...

f(5x) = -9(5x) +7

f(5x) = -45x +7

Step-by-step explanation:

mark me as brainliest ❤️

f(x) = -9x+7

f(5x)= -9(5x)+7

5x=-45x+7

-7=-45x/5x

-7=-9x

-7/-9 =x

x=0.7

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.

27 + 13x + 15 = (x + 5)( =

step-by-step explanation:

27 + 13x + 15 = (x + 5)( = 27 + 13x + 15 = (x + 5)( = 27 + 13x + 15 = (x + 5)( =