Answer:
Dan is 29. Cary is 36.
Step-by-step explanation:
Let Dan's age now be D.
Let Cary's age now be C.
"Cary is 7 years older than Dan."
C = D + 7
"In 7 years the sum of their ages will be 79. "
In 7 years, the ages of Dan and Cary will be D + 7 and C + 7, respectively.
D + 7 + C + 7 = 79
C + D + 14 = 79
C + D = 65
C = D + 7
The last two equations in bold above form a system of equations. Since the second equation is already solved for C, we use the substitution method.
D + 7 + D = 65
2D + 7 = 65
2D = 58
D = 29
C = D + 7
C = 29 + 7
C = 36
Answer: Dan is 29. Cary is 36.
17 - 6 x 10/2 + 12 =
17 - 60/2 + 12 =
17 - 30 + 12 =
-13 + 12 =
-1 <==
Answer:
49x^4-42x^2 y+9y^2
Step-by-step explanation:
<span>1/2(7x-8)+2x =2-(10x+4)
Distribute
(7x-8)/2 + 2x = 2 -10x -4
combine like terms
(7x - 8)/2 + 2x = -10x - 2
Multiply both sides by 2
7x - 8 + 4x = -20x -4
Combine like terms
11x - 8 = -20x - 4
add 8 to both sides
11x = -20x + 4
add 20x to both sides
11x + 20x = 4
combine like terms
31x = 4
divide both sides by 31
x = 4/31 or </span><span>0.129.
Hope this helps :)</span>
Step-by-step explanation:
wall 25×12=300
2 walls = 600
wall2 20×12=240
2 wall2= 480
600+480= 1080 sq ft