Answer:
b
Step-by-step explanation:
Answer:
A= 36
Step-by-step explanation:
a/4+2= A/6
36/6=6
Answer:
l = 7 in; w = 3 in
Step-by-step explanation:
The formula for the area of a rectangle is
A = lw
Data:
A = 21 in²
l = w + 4
Calculation:
21 = (w + 4) × w
21 = w² + 4w
w² + 4w - 21 = 0
(w + 7)(w - 3) = 0
w + 7 = 0 w - 3 = 0
w = -7 w = 3
We reject the negative value, so w = 3 in.
21 = l × 3
l = 7
The rectangle is 7 in long and 3 in wide.
А. х²-4=0; х²=4; х=±2, true.
B. x²=-4; there is no solution.
C. 3x²+12=0; 3x²=-12; x²=-4; there is no solution.
D. 4x²=16; x²=4; x=±2, true.
E. 2(x-2)²=0; 2(x²-4x+4)=0; 2x²-8x+8=0; x²-4x+4=0; x1=2; x2=2. False. The answer: A, D.