If she has 32 miles to the gallon, and 20 dollars, then 5*32 gives you your final answer, which is 160.
You have to make sure that whatever you do to one side, you also do to the other.
2x + 37 = 8x + 7
2x + 37 - 2x = 8x + 7 - 2x
37 = 6x + 7
37 - 7 = 6x + 7 - 7
30 = 6x
30 / 6 = 6x / 6
5 = x
x = 5
Hope this helps! :)
It looks like you want to find the short leg (x) of a right triangle with long leg 15 and hypotenuse 18. The Pythagorean theorem gives the relationship between the sides of a right triangle.
18² = 15² + x²
324 = 225 + x²
x² = 324 - 225 = 99
x = √99 ≈ 9.9
The appropriate choice is ...
b) 9.9
100 multiplied by two equal 200.
