Two mechanics worked on a car. The first mechanic worked for

Mathematics

2 answers:

ivann1987 [24]2 years ago

5 0

20x + 15y = 2000
x + y = 115
55+60=115

20 (55) + 15 (60)=2000
1100+900=2000
2000=2000

Ira Lisetskai [31]2 years ago

4 0

x=price per hour for first mechanic

y=price per hour for second mechanic

20x+15y=2000

x+y=115

solve

divide first equation by 5

4x+3y=400

multiply second equation by -3 and add to second

4x+3y=400
<u>-3x-3y=-345 +</u>
1x+0y=55

x=55

x+y=115

55+y=115

minus 55

y=60

first mechanic rage is $55 per hour

second mechanic is $60 per hour

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