Answer:
- Yolanda is 28
- Zachary is 21
Step-by-step explanation:
Let y represent Yolanda's age now, and let d represent their difference in ages. Then Zachary is now y-d years old.
When Yolanda was Zachary's age (now), Zachary was (y-d) -d. Yolanda is now twice that age:
y = 2(y -2d)
4d = y . . . . . . eliminate parentheses, add 4d-y
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When Zachary is as old as Yolanda is now, Yolanda will be y+d and the sum of their ages will be 63:
y + (y+d) = 63
2y + d = 63
Using the expression for y from above, we get ...
2(4d) +d = 63
d = 7 . . . . . . . . divide by 9
y = 4d = 28 . . . . Yolanda's current age
y-d = 21 . . . . . . . Zachary's current age
Jake spent a total of 70 cents.
b = black-and-white = 8 cents
c = color = 15 cents
70 = 8b + 15c
he made a total of 7 copies
b + c = 7
system of equation:
70 = 8b + 15c
b + c = 7
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b + c = 7
b + c (-c) = 7 (-c)
b = 7 - c
plug in 7 - c for b
70 = 8(7 - c) + 15c
Distribute the 8 to both 7 and - c (distributive property)
70 = 56 - 8c + 15c
Simplify like terms
70 = 56 - 8c + 15c
70 = 56 + 7c
Isolate the c, do the opposite of PEMDAS: Subtract 56 from both sides
70 (-56) = 56 (-56) + 7c
14 = 7c
divide 7 from both sides to isolate the c
14 = 7c
14/7 = 7c/7
c = 14/7
c = 2
c = 2
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Now that you know what c equals (c = 2), plug in 2 for c in one of the equations.
b + c = 7
c = 2
<em>b + (2) = 7
</em><em />Find b by isolating it. subtract 2 from both sides
b + 2 = 7
b + 2 (-2) = 7 (-2)
b = 7 - 2
b = 5
Jake made 5 black-and-white copies, and 2 color copies
hope this helps
Answer:
x-30
Step-by-step explanation:
Firstly, you do the first step, which is, 3x-18+4x+12-6x, then you continue simplifying it: 7x-18+12-6x.
Keep it on and on, the next step: x-18+12, add 18 and 12 together you get 30.
So the final answer is x-30
Answer:
D
Step-by-step explanation:
ΔWXZ and ΔYZX
WZ ≅XY {Given}
ZX ≅ ZX {Reflexive property}
∠W ≅ ∠Y
But for SAS congruent the congruent angles should between congruent sides( WX & WZ should be congruent to ZY & XY respectively).
So it cannot be proved using SAS congruent
Answer:
96
Step-by-step explanation:
144/12= 12 ( each hour)
12( times) 8=96
Since they got 144 for 12 hours you have to divide the hours by the money to get the amount earned ever hour so you divide the total amount by the hour then use the information you got and then you multiply the amount of money by 8