SOLUTION: the sum of twice a first number and five times a second number is 90. if the second number is subtracted from five times the second number the result is 36. find the numbers.

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Question 764802: the sum of twice a first number and five times a second number is 90. if the second number is subtracted from five times the second number the result is 36. find the numbers.
Answer by explodingstxrs(1) (Show Source):
You can put this solution on YOUR website!
Are you sure it's "the second number is subtracted from five times the second number"?
If so; let's make 1st number = A and 2nd number B
Elimination
2a + 5b = 90
5b - b = 36
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2a + 5b = 90...... (1)
0a + 4b = 36...... (2)
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In this case, we want to eliminate b (find the value of a) so multiply (1) with 4 and multiply (2) with 5
8a + 20b = 360
0a + 20b = 144
------------------------- -
8a = 216
a = 27
Substitute a to (1)
2(27) + 5b = 90
54 + 5b = 90
b = 36/5
b = 7,2
Hope this help :-)