Can someone me with this question

The triangles are similar. what is the value of x? enter your answer in the box. x = two right triangles. the larger right triangle is labeled x on the longer leg, 12 on the shorter leg and 20 on the hypotenuse. the smaller triangle is labeled 4 on the longer leg, 3 on the shorter leg, and 5 on the hypotenuse.

How is working backward similar to solving an equation?

Find the magnitude, correct to two decimal places, made by each of the following with positive direction of the x axis a) y= x the answer is 45° but i don’t know how