Let the number = x
Writing the equation you have:
10x + 15 <= -17
Solve for x
Subtract 15 from both sides:
10x <= -32
Divide both sides by 10:
X <= -32/10
Simplify:
X <= -16/5 as a fraction or -3.2 as a decimal
I believe that it would come out to become true
If you are implying that the triangles are similar, then the short and long legs are in proportion:

Solving for x, you have
