Hi Nicole,
From your description/ question for the parallelogram GRAM, I have the line segment AG as the diagonal.
Angle A is split into two parts. If you add up m<RAG and m<MAG you should get m<RAM.
You should know from parallelogram properties that adjacent angles are supplementary and opposite angles are congruent. We will be using the adjacent angles property and triangle sum theorem to find the value of x. Then you can substitute for x to find angle GMA
m<RAM + m<GMA = 180 as these are adjacent angles
2x+20+4(3x-1)+m<GMA =180
14x+16+m<GMA = 180 ------------------------------1
Triangle sum theorem
In triangle AMG, sum of angles = 180
4(3x-1)+2x^2+5x +m<GMA = 180------------------2
From 1 and 2,
14x+16+m<GMA=4(3x-1)+2x^2+5x+m<GMA
14x+16=4(3x-1)+2x^2+5x
14x+16=12x-4+2x^2+5x
2x^2+3x-20=0
Solving for x, you will get two values, take the positive value.
You will be able to find the value of <GMA by plugging in the value of x in eguation 1.
Hope this helps!
