SOLUTION: What number times another number equals 49 and the sum of 28?

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Question 807305: What number times another number equals 49 and the sum of 28?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

let a number be x and another number y
number times another number equals 49:
x%2Ay=49........eq.1
and the sum of 28:
x%2By=28........eq.2
solve the system:
x%2Ay=49........eq.1
x%2By=28........eq.2
__________________________
x%2By=28........eq.2.....solve for x
x+=28-y........eq.2a.....substitute in eq.1

%2828-y%29%2Ay=49........eq.1...solve for y
28y-y%5E2=49
0=y%5E2-28y%2B49......use quadratic formula

y+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
y+=+%28-%28-28%29+%2B-+sqrt%28+%28-28%29%5E2-4%2A1%2A49+%29%29%2F%282%2A1%29+
y+=+%28+28++%2B-+sqrt%28+784-196+%29%29%2F2+
y+=+%28+28++%2B-+sqrt%28+588+%29%29%2F2+
y+=+%28+28++%2B-+24.25%29%2F2+
solutions:
y+=+%28+28++%2B+24.25%29%2F2+
y+=+26.125
y+=+%28+28++-24.25%29%2F2+
y+=+1.875
now find x+=28-y........eq.2a
x+=28-26.12
x+=1.875
or
x+=28-1.875
x+=26.125
so, one solution is x+=1.875 and y+=+26.125
and another is vs, x+=26.125 and y+=+1.875
check:
x%2Ay=49........eq.1=>1.875%2A26.125=48.984375...rounded 49
x%2By=28........eq.2=>1.875%2B26.125=28