Given the figure below, find the values of
x
and
z
.
z°
81°
+11x44°
x
=
z
=
81

Https://tex.z-dn.net/?f=+%5Cfrac%7B8%7D%7B64%7D+%3D+%5Cfrac%7B2%7D%7Bx%7D++%5C%5C++%5C%5C+8x%3D128+%5C%5C++%5C%5C+x%3D16

Let's make a system of equations.
F=First mechanic
S=Second mechanic
F+S=20
85F+120S=1875
Let's make the first equation equal S.
S=20-F; We can plug this in as S in the second equation.
85F+120(20-F)=1875
85F+2400-120F=1875
Add like terms.
-35F+2400=1875
Subtract 2400.
-35F=-525
Divide.
-525÷-35=15=F
So, the first mechanic worked 15 hours and the second one had to work 5 since they worked 20 together. Let's check.
85(15)+120(5)
1,275+600
1,875
So, the first mechanic worked 15 hours and the second mechanic worked 5 hours.