Answer/Step-by-step explanation:
Area of trapezium = ½*(AD + BC)*AB
Area = 42 cm²
AD = (x + 8) cm
BC = (x + 5) cm
AB = x cm
Plug in the values into the equation
42 = ½((x + 8) + (x + 5))*x
42 = ½((x + 8 + x + 5)*x
42 = ½(2x + 13)*x
Multiply both sides by 2
42*2 = (2x + 13)*x
84 = 2x² + 13x
2x² + 13x = 84
Subtract both sides by 84
2x² + 13x - 84 = 0
Answer:
Step-by-step explanation:
Let x represent the number of hours that that he spent washing cars.
Let y represent the number of hours that that he spent landscaping.
In a week, he can work no more than 19 total hours. This means that
x + y ≤ 19- - - - - - - - - - - -1
Jacob is working two summer jobs, making $10 per hour washing cars and making $8 per hour landscaping. He must earn at least $170. This means that
10x + 8y ≥ 170 - - - - - - - - - -2
If Jacob worked 4 hours landscaping, it means that
x + 4 ≤ 19
x ≤ 19 - 4
x ≤ 15
Also,
10x + 8 × 4 ≥ 170
10x + 32 ≥ 170
10x ≥ 170 - 32
10x ≥ 138
10x ≥ 138/10
x ≥ 13.8
The minimum number of hours is 14
Answer:
Step-by-step explanation:
w - width
6w - length
486 in² - area of the rectangle
(w)(6w) = 6w² - area of the rectangle
The equation:
6w² = 486 <em>divide both sides by 6</em>
w² = 81 → w = √81
w = 9 in
l = 6w → l = (6)(9) → l = 54 in
The perimeter: P = 2l + 2w
P = 2(54) + 2(9) = 108 + 18 = 126 in
<h3>Answer: The perimeter is 126in</h3>
