You use the Pythagorean theorem which is a^2+b^2=c^2
So....
.8^2+.6^2=c^2
.64+.36=c^2
1=c^2
1=c becaaue the square root of one is one
The answer is one hundred and thirty one
(-2d^2+s)(5d^2-6s)
= (-2d^2*5d^2 + s*5d^2 -2d^2*-6s + s*-6s
= -10d^4 + 5sd^2 + 12sd^2 - 6s^2
=-10d^2 + 17sd^2 - 6s^2
This is the final result
The answer is 93. its very simple to round well mosly for me cause im smart