7(3x + 5y)
Simplify this expression please!

Agroup of students want to create a garden. they do not know the exact measurements but they propose using a variable to represent the length and width of the garden. the length of the garden is 10 feet longer than double the width. use a single variable to write algebraic expressions for both the length and width of the garden. write an algebraic expression for the area of the garden. use mathematical terms to describe this expression.

Geometry in the diagram, ∠abc is a right angle. ∠dbc = 30°27'40". find the measure of ∠abd.

Ahiker stands at an unknown elevation before he ascends 2 miles up a mountain to an elevation of 9 miles. find the elevation of the hiker before his ascent.