(-7.5+1.7):2.9

To solve this expression, first we perform the division inside the parentheses:

(-7.5 + 1.7) ÷ 2.9

Now we add the numbers inside the parentheses:

= (-5.8) ÷ 2.9

Now we perform the division:

= -2.0

Therefore, (-7.5 + 1.7) ÷ 2.9 = -2.0