(-42) (-29) (-28)
-42 - 29 = -71
-71 - 28 = -99
-99 is your answer
hope this helps
To find percent error you use the following formula:

% error = (1.6 - 1.9)/1.9 * 100% = 15.79%
By using the Distributive Property, you would multiply 3 into the parenthesis (3 · x and 3 · -4)
3(x - 4) = 24
3x - 12 = 24
Then, you would solve like any normal one-step equation.
3x - 12 = 24
+12 +12
__________
3x 36
__ = __
3 3
x = 12, which is your final solution.
If you need any further explanations, please ask me :)
Let x represent the number of pounds of $10.75/lb coffee used in the mix.
.. 10.75x +3.25(100 -x) = 5.65*100 . . . . . . total cost of coffee blend
.. x(10.75 -3.25) = 100*(5.65 -3.25) . . . . . .separate x-terms from non-x terms
.. x = 240/7.5 = 32
32 pounds of $10.75/lb coffee should be used
68 pounds of $3.25/lb coffee should be used