20 points and brainliest Pls help er

Use the elimination method to solve the systems of equations.choose the correct ordered pair. 7x+4y=39

The perimeter of a quarter circle is 14.28 miles. what is the quarter circle's radius?

He trapezoid is composed of a rectangle and two triangles. what is the area of the rectangle? what is the total area of the triangles? what is the area of the trapezoid? ? a) 42 cm2; 27 cm2; 69 cm 2 b) 54 cm2; 27 cm2; 81 cm 2 c) 108 cm2; 27 cm2; 135 cm 2 d) 108 cm2; 13.5 cm2; 121.5 cm 2