Let
x = number of minutes of local calls.
y = number of minutes of international calls.
By writing the system of equations we have:
0.06x + 0.15y = 69.84
x + y = 852
Solving the system
Clear y from equation two
y = 852-x
Replace y in equation 1
0.06x + 0.15 (852-x) = 69.84
Clear x
0.06x + 127.8 - 0.15x = 69.84
127.8 - 69.84 = 0.15x -0.06x
57.96 = 0.09x
x = 57.96 / 0.09 = 644
x = 644
Replace x in any of the two equations and clear y:
x + y = 852
y = 852-644
y = 208
answer
number of minutes of local calls = 644
number of minutes of international calls = 208
A.....72
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Solve for h by simplifying both sides of the equation, then isolating the variable.
h=a/2+1-3/a
4;81
You subtract 5 from 9 to get 4; 5(9)= 45 9(4)=36 45+39=81
