Answer:
-6x-4
Step-by-step explanation:
Combine 6x and −12x to get −6x.
−6x−7+3
Add −7 and 3 to get −4.
−6x−4
Answer:
um i dont know
Step-by-step explanation:
Let x be the amount of cement and y be the amount of sand. If <span>the ratio of cement to sand for mortar is 1:3, then

and y=3x.
</span>
So, if <span>Sandy puts in x=7 shovels of cement, then she puts

shovels of sand.
</span><span>
</span><span>
Answer: 21 shovels of sand.
</span>