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Find the difference (8ab+a+2) - (3ab+6)

The construction of copying qpr is started below. the next step is to set the width of the compass to the length of ab. how does this step ensure that a new angle will be congruent to the original angle? by using compass take the measures of angle and draw the same arc according to it.

Simplify 1 divided by 2/3 x (-3) divided by 1/6 x (-10)