Answer:
x = 7000
y = 5600
(7000, 5600)
Step-by-step explanation:
To solve the system of equations means to find the point of intersection (graphically). You are finding what value of 'x' and what value of 'y' fits both equations.
x = y + 1400
0.08x + 0.05y = 840
We can solve using the method <u>substitution</u>, where you replace a variable in one equation with an equivalent expression.
<u>Since "x" is y + 1400, we can replace "x" in the second equation.</u>
0.08x + 0.05y = 840
0.08(y + 1400) + 0.05y = 840
Distribute over brackets by multiplying 0.08 with y, then 0.08 with 1400.
0.08y + 112 + 0.05y = 840 Collect like terms (with "y" variable)
112 + 0.13y = 840
Now isolate "y" in the simplified equation.
112 - 112 + 0.13y = 840 - 112 Subtract 112 from both sides
0.13y = 728
0.13y/0.13 = 728/0.13 Divide both sides by 0.13
y = 5600 Solved for y
We can substitute "y" with 5600 in any other equation that has "x".
x = y + 1400
x = 5600 + 1400 Add
x = 7000 Solved for x
You may express the answer as a coordinate, or an ordered pair (x, y).
The solution is (7000, 5600).
