Let t represent Todd's age now.
.. 4(t -3) -(t -3) = 81 . . . . . . 3 years ago, their differnce in ages was 81.
.. 3t -9 = 81
.. t = (81 +9)/3 = 30
Todd is 30 now.
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You can also work this by considering "ratio units." 3 years ago, the ratio of their ages was 4:1, a difference of 3. That difference corresponds to 81 years, so each "ratio unit" represents 81/3 = 27 years. Todd's age then was 1 ratio unit, 27 years. Now, Todd's age is 30.
2x - 3y = 3.....multiply by 4
5x - 4y = 4....multiply by -3
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8x - 12y = 12 (result of multiplying by 4)
-15x + 12y = -12 (result of multiplying by -3)
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- 7x = 0
x = 0 <===
Answer:
a) X=0
b) X=2,-2
Step-by-step explanation:
Y=-4x+10
I hope this helped you
