3. Problem three wants you top find the perimeter of a triangle, you can find the perimeter by adding all of the side lengths together.
P = (5x - 7) + (3x - 4) + (2x - 6) Remember to add like-terms, start with all the numbers with x next to them.
P = (5x + 3x + 2x) + (-7 + -4 + -6)
P = (10x) + (-17) Then, combine them back into one equation.
P = 10x - 17, so answer choice A.
4. The problem wants you to find the volume of the driveway, which is how much concrete will fit in it. You can find the volume with the equation (volume = width x height x length).
V = W x H x L Substitute the variable for the dimensions. (height = depth)
V = 6 x 1/3 x 162 I changed 4 inches to 1/3 ft so that all the values will be in feet.
V = 2 x 162
V = 324 ft³, so answer choice B.