I honestly don’t know. But the square in the bottom of the triangles indicate that it is a right triangle equaling 90 degrees. You can try using that along with other knowledge of right triangles you have. Could you possibly use Pythagorean theorem also?
Step-by-step explanation:
2/5×7500
2×1500
3000
RM=3000
1.sometimes
2. always
3.never
2x + y = 5
x − 2y = 10
y = 5 − 2x
x − 2(5 − 2x) = 10
x − 10 + 4x = 10
5x − 10 = 10
<em>add 10 to each side</em>
<em>5x-10+10 = 10 + 10</em>
<em>5x=20</em>
5x = 0 <em>this is the error</em>
He needs to add 10 to each side