Answer:
x= 6
Step-by-step explanation:
Let x= number rows
Then x + 5 = number of seats per row
x(x+5) = 126
X^2 + 5x = 126
x^2 + 5x -126 = 0; now factor or use quadratic:
(x+14)(x-9) = 0; so the answers are either -14, or 9, and since -14 is not possible in this case because you can't have a negative number of rows, the answer is 9 rows.
Check work: number of rows = 9, number of seats per row = 9+ 5= 14, and 9 x 14 = 126
Answer:
19/20 is the correct answer
The rest of the question is the attached figure.
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Δ AYW a right triangle at Y ⇒⇒⇒ ∴ WA² = AY² + YW²
And AY = YB ⇒⇒⇒ ∴ WA² = YB² + YW² → (1)
Δ BYW a right triangle at Y ⇒⇒⇒ ∴ WB² = BY² + YW² → (2)
From (1) , (2) ⇒⇒⇒ ∴ WA = WB →→ (3)
Δ CXW a right triangle at Y ⇒⇒⇒ ∴ WC² = CX² + XW²
And CX = XB ⇒⇒⇒ ∴ WC² = XB² + XW² → (4)
Δ BXW a right triangle at Y ⇒⇒⇒ ∴ WB² = XB² + XW² → (5)
From (4) , (5) ⇒⇒⇒ ∴ WC = WB →→ (6)
From (3) , (6)
WA = WB = WC
given ⇒⇒⇒ WA = 5x – 8 and WC = 3x + 2
∴ <span> 5x – 8 = 3x + 2</span>
Solve for x ⇒⇒⇒ ∴ x = 5
∴ WB = WA = WC = 3*5 + 2 = 17
The correct answer is option D. WB = 17