Since you need an isolated variable to use the substitution method, we need to re-arrange one of the equations. This will probably be easiest to do with the first one.
Add 5y to both sides of the first equation.
x=10+5y
Now, in the second equation, put in 10+5y in any spot that has an x.
2(10+5y)-10y=20
Distribute the 2 to both numbers in the parenthesis.
20+10y-10y=20
Combine like terms.
20=20
This means that the two equations are actually the same. You can see this if you multiply the whole first equation by 2
2(x-5y=10)
2x-10y=20, which is the same as the second equation. Therefore, the two equations are actually the same one.
<span>Here is the answer, hope this helps
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Answer:
Let Ishaan's age be x. Then, Christopher's age is x-20. These are their current ages.
14 years ago,
x-14 = 3(x-20-14) (we need to subtract 14 from both of their ages')
x - 14 = 3(x - 34)
x - 14 = 3x - 102
2x = 88
x = 44
Ishaan is 44 years old now.
Yes, 15 for both sides and 7 for the bottom. It will make an Acute Isosceles Triangle.
