Answer:
144 ft^2
Step-by-step explanation:
Back (vertical): (4 ft)(8 ft) = 32 ft^2
Right side (vert.): (4 ft)(6 ft) = 24 ft^2
Front (vert.): (4 ft)(10 ft) = 40 ft^2
Top (horizontal): A = (1/2)(6 ft)(8 ft) = 48 ft^2 total (top and bottom)
Total surface area is (32 + 24 + 40 + 48) ft^2, or 144 ft^2
Width of a rectangle is half its length:
2w = l
Perimeter is 36
2w + 2l = 36
Plug first equation into second (substitution)
2w + 2(2w) = 36
2w + 4w = 36
6w = 36
w = 6
Plug back into first equation to solve for l
2(6) = 12 = l
Answer: D
Step-by-step explanation:
(7x -7) + (6x +6) = 90
take away the parenthesis: 7x - 7 + 6x + 6 = 90
combine like terms: 13x - 1 = 90
add 1 to both sides: 13x = 91
divide both sides by 13: <span>x = 7.
Now: substitute x = 7 into the angles: the first angle is 42 degrees, the second angle is 48 degrees</span>
