Solving systems by substitution:

y=5x-10

y=3x+8

I dont underatand how to solve it

Felipe finished his history assignment in 2/5 hours. Then he completed his math assignment in 3/4 hours. How much more time did Felipe spend on his math assignment?

What is the center and radius of the circle (x-4) ² + (y) ² = 16

Estimate the area of a circle. use 22/7 for pi

What is one quarter added to one eighth

Since January 1980, the population of the city of Brownville has changed according to the equation y=720,500 (1+.022) ^x, where ^ indicates exponent. What does the number. 022 represent?

5x+12=44 then value of 5x-12=?

Which is greater, the amount the average person spends in a month on coffee or the amount the average person spends in a month on gasoline?

Using completing the square solve for x X^2-10x-9=0

Brazil exports the most coffee in the world. It cost approximately $2.55 to produce a pound of coffee; they want to make a profit of 300% for each pound. Also, the U. S. charges a 20% Tariff for each pound that is imported.

You buy hats for $5 and sell them for $20 each. what dose the graph of profits as a function of the number of the hats sold look like