Make 3 two digit numbers and 1 single digit number using 1, 2, 3, 4, 5, 6, 7 and add them together to make 100?

Question

1 2 3 4 5 6 7 8 9 = 100
Challenge:
Place + and - math symbols between the numbers above to make the equation true.
Use + and - a total of three times.
Do not rearrange the numbers.

Answer 1

45+32+17+6=100.