What rule was to create this pattern? 3,8,13.18?

Find the values of the variables in the kite

2x minus y equals 6, x plus y equals negative 3

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.