Answer:
(8 - 12 )
Step-by-step explanation:
Given
x - 
y = 8
x + 
y = - 5
Multiply both equations through by 4 to clear the fractions
x - 2y = 32 → (1)
2x + 3y = - 20 → (2)
Multiplying (1) by - 2 and adding to (2) will eliminate the x- term
- 2x + 4y = - 64 → (3)
Add (2) and (3) term by term to eliminate x
0 + 7y = - 84
7y = - 84 ( divide both sides by 7 )
y = - 12
Substitute y = - 12 into either of the 2 equations and solve for x
Substituting into (1)
x - 2(- 12) = 32
x + 24 = 32 ( subtract 24 from both sides )
x = 8
solution is (8, - 12 )
864000cm squared to meters squared would be 8.64
1. 2(4) - 4y = 20
8 -4y = 20
8-8 -4y = 20 - 8
-4/-4y = 12/-4
y = -3
Answer: the length is 11 cm.
The width is 7 cm.
Step-by-step explanation:
Let L represent the length of the rectangular plastic box.
Let W represent the width of the rectangular plastic box.
The area of the rectangular top of the box is 77 square cm. This means that
LW = 77- - - - - - - ;- - - -1
The plastic box has a length 4 cm longer than its width. This means that
L = W + 4
Substituting L = W + 4 into equation 1, it becomes
(W + 4)W = 77
W² + 4W = 77
W² + 4W - 77 = 0
W² + 11W - 7W - 77 = 0
W(W + 11) - 7(W + 11) = 0
W - 7 = 0 or W + 11 = 0
W = 7 or W = - 11
Since the width cannot be negative, then W = 7cm
L = 77/7 = 11 cm
