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.
Answer:
4 hours
Step-by-step explanation:
Let x = # of hours
22x + 10 = 98
-10 -10
____________
<u>22x = 88</u>
22
x = 4
Solve the top equation for x and then substitute that into the bottom equation and solve for y:
Top equation: subtract 4 from both sides to get x = y - 4
Substitution and simplify:
y = 4(y - 4) - 10
y = 4y - 16 - 10
y = 4y - 26
-3y = -26
y = 26/3 or 8 1/3 or 8.333 (those are all the same but in different forms)
Answer:[7,2]
Step-by-step explanation:
If 3/8 equals 3 ft, then i would assume that 5/8 equals 5 ft.
