The answer is C.
You need you use Pythagoras theorem 2 times to have 2 equations with the same sides i.e. for example a2 + b2 = 81 and a2 - b2 = 9.
You can do it as you have different triangles but with the same sides.
Total ratio = 4+7 = 11
33/11 = 3
4x3 = 12
7x3 = 21
so the two groups are 12:21
which is also = 4:7
Subtract L from both sides.
the expression now becomes,
<span>S−L=−rL</span>
2)Divide by L on both sides.
<span><span><span>S−L</span>L</span>=−r</span>
3)Multiply with a negative sign on both sides in the final step to obtain the expression in terms of r so the answer is<span> #(L-S)/L = r#</span>
27 divided by 15 is 1.8, so that should be the correct answer.
The sum of three consecutives is b