F(5) = 2(5)^2 - 10
f(5) = 2(25) - 10
f(5) = 50 - 10
f(5) = 40
It's because a tenth means that you've divided it by 10. So if it's 20, it means you're multiplying tenths by 20, leaving you with 2 wholes.
For example, you have 2 cakes and you cut each into 10 slices, the slices are each one tenth of the whole cake, and in total there are 20 tenths.
Try this option:
1. the sides of the biggest triangle are 16; x and √(16²-x²); the sides of the smallest triange are x;5 and y. The smallest triangle ~ the biggest triangle. Using the property of the similar triangles:

2. according to the Pyphagorean theorem (in the smallest triangle):

answer: y=√55.
Answer:
93
Step-by-step explanation:
15 x 5 = 75 + 18 = 93