Answer:
Step-by-step explanation:
lets say "a" for the empty line,
for small triangle; y^2 = 2^2 + x^2
right triangle; we say a for empty line, a^2= 6^2 + x^2
and big triangle covering both triangles, 8^2 = y^2 + a^2
lets add left sides and right sides in each;
x^2 + 4 + x^2 + 36 + y^2 + a^2 = y^2 + a^2 + 64 and we can delete same things for both sides
y^2 and a^2 can be deleted and 4+36 - 64
2(x^2)=24
x^2= 12
and x will be √12
so, y^2 = x^2 + 2^2 which means y^2 = 12+4 y=16
If Simone has 20 bills, then:
1/5 of 20 = 4 [hundreds]
1/4 of 20 = 5 [fifites]
1/10 of 20 = 2 [$20s]
4 * 100 + 5 * 50 + 2 * 20 = 400 + 250 + 40 = 690 [out of $780]
4 + 5 + 2 = 11 [out of 20 bills]
So now we can easily find out she had 9 bills of tens - because 20 - 11 = 9 or because (780 - 690) ÷ 10 = 90 ÷ 10 = 9.
