Answer:
x = 45
Step-by-step explanation:
Corresponding sides of similar triangles will be in same ratio.

Cross multiply
x*28 = 20*(x+18) {Use distributive method}
28x = 20x + 360
28x - 20x = 360
8x = 360
x = 360/8
x = 45
The first step I would take is
.. Multiply both sides of the equation by 1/4.
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You could start by adding 16 to both sides of the equation, to make the left side the square (2x +4)^2.
Answer is 20.3 and the steps are:
1.) 7 x 9 = 63 move the six over the 2 leave the 3 down
2.) 7 x 2 = 14
3.) 14 + 6 = 20
4.) you have 203 but must bring the decimal down and it makes it: 20.3
I hope I helped and if you're confused please ask questions
The answer will be around 145