Help please

The sum of two numbers is 12 and their difference is 18 what are the two numbers

Valentina is subtracting from . she finds the lcd to be 15y2. what is valentina's next step?

(05.02) mr. morris is going to save money and replace his sailboat's mainsail himself. he must determine the area of the mainsail in order to buy the correct amount of material. calculate the area of the parallelogram to determine how much material should be purchased. be sure to explain how to decompose this shape into rectangles and triangles. describe their dimensions and show your work.