Answer:
<h2>x = 10.1</h2>
Step-by-step explanation:
<h2>
Length = 3m</h2><h2>
Width = 5m</h2><h3>
State where x is accordingly.</h3><h2>
</h2>
The length of a rectangle is seven less than twice the length of its width.
L = 2W - 7
A = W * L
A = 15
15 = W * L
Substitute the L in terms of W
15 = W * (2W - 7)
15 = 2W^2 - 7W
2W^2 - 7W - 15 = 0
Factorise:
(2W + 3) (W - 5) = 0
Solve for W:
2W + 3 = 0
2W = 0 - 3
2W = 3
W = 3/2
W = 1.5
W - 5 = 0
W = 0 + 5
W = 5
Use the original equation to find L:
L = 2W - 7
L = 2(5) - 7
L = 10 - 7
L = 3
L * W = 15
3 * 5 = 15
X^2 + kx + 15 = 0
3^2 + 3k + 15 = 0
9 + 3k + 15 = 0
24 + 3k = 0
3k = -24
k = -24/ 3
k = -8
The answer 5 (1/4) because if you add 1 and a quarter to it then that would make it 6 and a half
