The sum of 3 integers is 194. the sum of the first and second integers exceeds the third by 80. the third integer is 45 less than the first. find the three integers

Let
x = first integer
y = second integer
z = third integer
First equation: x + y + z = 194
Second equation: x + y = z + 80
Third equation: z = x - 45

Let's find the values of x, y and z.
Substitute 3rd eq to 1st eq:
x + y + x - 45 = 194
2x + y = 45 + 194
y = -2x + 239

Plug in both we have solved for y and the 3rd eq to the 2nd eq to find x
x + (-2x + 239) = (x - 45) + 80
x - 2x - x = -45 + 80 - 239
-2x = -204
x = -204/-2
x = 102

Solving for y,
y = -2(102) + 239
y = 35

Solving for z,
z = 102 - 45
z = 57