Since if he gets the driveway done in 20 minutes he gets 1/20th of the driveway done in 1 minute (if x=20 then x/20=1 by dividing both sides by 20) and if his brother gets 1/12th of the driveway done in one minute, then if t represents the time it takes to shovel the driveway, t/20+t/12=1 driveway shoveled as 1/20+1/12=amount they can do in 1 minute, so t/20+t/12 is how much they can do in t minutes. Multiplying both sides by 20*12=240, we get 12t+20t=32t=240. Dividing both sides by 32, we get 240/32=7.5 minutes to shovel the driveway.
Answer:
b
Step-by-step explanation:
in certain economies, the government operates as the central authority, guiding the economy and controlling (and owning) many of the businesses. Instead of being produced to make a profit, goods and services are produced for uses planned by the government. What type of economy does this describe? A. gift economy B. market economy C. socialist economy D. laissez-faire economy
10x^4y^4+2x^6-15y^6-3x^2y^2
Answer:
y=-2x^2+10x-12
Step-by-step explanation:
graph is shown in image below