2x+y=-11; 3x-4y=11

How do I solve this by substitution?

You buy a board that measures 120 inches long. How many eight-inch sections can you cut from this board?

Bella has 6.3 kilograms of berries. She packs them 0.35 kilogram of berries into each container. A. How many containers will she fill? B. She then sells each container for 2.99. How much will Bella earn if she sells all the containers?

In a cookie jar, 1/4 of the cookies are chocolate chip and 1/2 of the rest are peanut butter. what fraction of all the cookies are peanut butter?

Clara simplifies (8 b minus 4 r) minus (2 b minus r) and says the result is 6 b minus 5 r. What error did Clara make? Clara incorrectly combined the b coefficients. The correctly simplified expression is 10 b minus 5 r.

Circle the error and explain why it is an error. Given 5 (8 - 3x) = 5x + 70

Quincy is using 320 pieces of stone tile to make red white and blue mosaic. If 20% of the pieces are blue and 35% are white how many pieces are red?

Identify the amplitude and the period of the function c (x) = 3cos (x + π).

Suppose that a cell phone monthly rate plan costs the user 5 cents per minute beyond a fixed monthly fee of $20. This implies that the relationship between monthly cost and monthly number of minutes is linear.

Riki rides her bike 26 miles every week. What is the total numbers of miles she will ride in one dozen. What is the total number of miles she will ride in 7 weeks

Atherine has $54. She plans to spend more than $20 of the money for a painting canvas. The rest will go toward paints. Each tube of paint costs $8.50. Assume that x represents the number of tubes of paint Catherine can buy.