Answer:
<h2>Length: 18 yd, Width: 5.5 yd</h2>
Step-by-step explanation:
w - width
2w + 7 - length
99 yd² - area of a rectangle
The formula of an area of a rectangle:
A = lw
l - length
w - width
Substiute:
w(2w + 7) = 99 <em>use the distributive property</em>
2w² + 7w = 99 <em>subtract 99 from both sides</em>
2w² + 7w - 99 = 0
2w² + 18x - 11x - 99 = 0
2w(w + 9) - 11(x + 9) = 0
(w + 9)(2w - 11) = 0 ⇔ w + 9 = 0 or 2w - 11 = 0
w + 9 = 0 <em>subtract 9 from both sides</em>
w = -9 < 0 !!!
2w - 11 = 0 <em>add 11 to both sides</em>
2w = 11 <em>divide both sides by 2</em>
w = 5.5 yd
2w + 7 = 2(5.5) + 7 = 11 + 7 = 18 yd
<em />
Y² + 14y + 49 = 0
We know a² + 2ab + b² = (a + b)²
(y)² + 2 x 7 x y + (7)² = 0
(y + 7)² = 0
y = -7
y = -7
Correct option C
Answer:
90°, 78°, 12°
Step-by-step explanation:
let the third angle be x then the second angle is 7x - 6
Since 1 of the angles in the triangle is 90° then the second and third angles sum to 90° , then
x + 7x - 6 = 90
8x - 6 = 90 ( add 6 to both sides )
8x = 96 ( divide both sides by 8 )
x = 12
Then
second angle = 7x - 6 = 7(12) - 6 = 84 - 6 = 78°
The 3 angles are 90°, 78°, 12°
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