What does the symbol EF in the formula indicate that Chang
needs to do?
He needs to find the net force acting on the object in a
direction.
He needs to use only forces acting in the direction of
motion.
He needs to combine the horizontal and vertical forces.
He needs to multiply the horizontal and vertical forces.

both triangles are similar because 2 is just smaller than the big one 1 is similar because they are facing different way's but are similar to each other

step-by-step explanation:

answer: c

substitute in the values.

for a:

f(0) = 0 + 9

f(0) = 9

a is a solution.

for b:

f(7) = 14 + 9

f(7) = 23

b is a solution.

for c:

f (3) = 6 + 9

f(3) = 15

c is not a solution. it's supposed to be 14.

for d:

f(2) = 4 + 9

f(2)= 13

d is a solution.