Someone please help me with number 5 plz and thank you :)

The sixth grade art students are making a mosaic using tiles in the shape of right triangles.each tile has leg measures of 3 centimeters and 5 centimeters.i f there are 200 tiles in the mosaic what is the area of the mosaic.

Susie wants to take her friend out for lunch.she wants to spend $9.75 each person. how much will she spend in all.

Which shows the first equation written in slope-intercept form? 1/2 (2y + 10) = 7x