Test 2 Review 8th Grade (1st)

Front

What does it mean for the cost of electricity to vary directly with the amount of kilowatt-hours used?

Back

It means that as the number of kilowatt-hours increases, the cost increases proportionally. If you use twice the kilowatt-hours, the cost will also be twice as much.

Front

If 1,079 kilowatt-hours costs $129.48, how do you find the cost for 908 kilowatt-hours?

Back

Use the ratio of the costs to the kilowatt-hours: Cost per kilowatt-hour = $129.48 / 1,079. Then multiply this cost per kilowatt-hour by 908.

Front

What is a function in mathematics?

Back

A function is a relation that assigns exactly one output for each input. For example, if c is the total cost and n is the number of pieces of candy, c = 0.42n if each piece costs $0.42.

Front

What does it mean for two triangles to be similar?

Back

Two triangles are similar if their corresponding angles are equal and their corresponding sides are in proportion.

Front

How do you represent a proportional relationship mathematically?

Back

A proportional relationship can be represented by the equation y = kx, where k is the constant of proportionality.

Front

What is the slope of a line?

Back

The slope of a line is a measure of its steepness, calculated as the rise (change in y) over the run (change in x).

Front

What does the equation y = 3x + 5 represent?

Back

This is the equation of a line in slope-intercept form, where 3 is the slope and 5 is the y-intercept.

Front

What is a coupon in the context of shopping?

Back

A coupon is a voucher that provides a discount on the purchase price of a product.

Front

How do you calculate the total cost after using a coupon?

Back

Total cost = Original price - Discount from coupon.

Front

What is a table of values in mathematics?

Back

A table of values is a way to organize pairs of input and output values, often used to represent a function.