Help please! I need help

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

Apolygon is shown on the graph: a polygon is shown on the coordinate plane. vertices are located at 3 comma 5, 1 comma 3, 1 comma 1, 2 comma 0, 4 comma 0, 5 comma 1, and 5 comma 3. what effect will a translation 3 units down and 2 units left have on the polygon? be sure to address how it could impact the angles, side lengths, and congruency between the original pre-image and the image. xd i need