What is 20/16=d/12? what equals d?

  d = 15

Step-by-step explanation:

Divide the numbers

Multiply all terms by the same value to eliminate fraction denominators

Cancel multiplied terms that are in the denominator

Multiply the numbers

Move the variable to the left

Hence, d= 15.

[RevyBreeze]

rectangle: 9 1/8 x 4 1/9 = 37 37/72in

parallelogram: b times h= 10.3 x 6.2 = 63.86

trapezoid: a+b/2 times h= 42.5

volume of prism: l times w times h= 36

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.