Ineed with finding x's value. it's geometry. see attachment

The marks on the line segments tell you they are the same length, and that the triangle is an equilateral triangle. That tells you the angles are the same size, and all are 60°. This lets you find x and y.

(7x+4)° = 60°

7x = 56 . . . . . . . . divide by °, subtract 4

x = 8 . . . . . . . . . . divide by 7

(8y+12)° = 60°

8y = 48 . . . . . . . . divide by °, subtract 12

y = 6 . . . . . . . . . . divide by 8

c.   x=2.4cm

step-by-step explanation:

similar triangles are triangles which have the same shape but not the same size. this means their angle measures are equal but their side lengths are not instead they are proportional. to solve, we will set up a proportion and solve.

a proportion is two equal ratios set equal to each other. we form the ratios by finding corresponding sides (sides which match to each other on both triangles by their position). out ratios will be one side of the small triangle over the corresponding side on the big triangle as shown below:

.

to solve the proportion, we'll cross multiply by multiplying numerator with denominator across the equal sign.