Step-by-step explanation:
E3, E6, E11, E7: no solution
E1, E12 : 1 solution
E2, E8, E10 : infinite solutions
I'm pretty sure the answer to your question is -3/5 + 4/5. C.
Answer:
Alisa practiced for 240 minutes (4 hours). In total, they practiced for 288 minutes (4.8 hours).
Step-by-step explanation:
If James practiced for 48, and Alisa practiced 5 times as long, then we would multiply 48 by 5 (240 minutes).
If we want to find how many minutes in total they practiced, then we would add 240 minutes (Alisa's practice time) and 48 minutes (James' practice time) together, which would equal 288 minutes (4.8 hours).
Equation: y=48+x
Finding x:
If y=2x+9, substitute y into the equation x-3y=-12.
You will get: x-3(2x+9)=-12
Now, distribute: x-6x-27=-12
Add like terms: -5x-27=-12
Add 27 to both sides: -5x=15
Divide both sides by -5: x=-3
Now, substitute this value of x into the equation to find y: y=2(-3)+9
Multiply: y=-6+9
Add: y=3
Here is the solution: (x,y)=(-3,3)
Hope this explanation helped!