The formula for a rectangle's perimeter is
P = 2l + 2w
We know the length is 2 ft greater than thrice the width, so 2l becomes:
3w + 2ft + 3w + 2ft
Substitute.
P = 3w + 2ft + 3w + 2ft + 2w
Add like terms.
P = 8w + 4ft
Substitute P.
84 ft = 8w + 4ft
Subtract 4 ft from both sides to eliminate. (Property of equality)
84 ft - 4ft = 8w + 4ft - 4ft
80 ft = 8w
Divide 8 on both sides to isolate w.
80 ft / 8 = 8w / 8
10 ft = w
We have the value of w, now look for the l which we know is 2 feet more than thrice the value of w.
l = 10 ft × 3 + 2 ft
l = 30 ft + 2 ft
l = 32 ft
Therefore, the length and the width of the rectangle is 10 ft (w) and 32 ft (l).
Check:
84 ft = (2) (10 ft) + (2) (32 ft)
84 ft = 20 ft + 64 ft
84 ft = 84 ft ✔
♧
The square root of 400 is 20. Please give me brainliest
3 and 5/8
three and five eighth
Answer:
Area of triangle formula:
A = b*h/2
B is 18 and h is 13
B is base and h is height.
18 * 13 is 234.
We must divide by two because just multiplying the two numbers would result in an area of a square, divide by 2 for a triangle.
234/2 =
117 km²
