Answer:
Step-by-step explanation:
What we have is a general equation that says this in words:
Laura's hours + Doug's hours = 250 total hours
Since we don't know either person's number of hours, AND since we can only have 1 unknown in a single equation, we need to write Laura's hours in terms of Doug's, or Doug's hours in terms of Laura's. We are told that Doug spent Laura's hours plus another 40 in the lab, so let's call Laura's hours "x". That makes Doug's hours "x + 40". Now we can write our general equation in terms of x:
x + x + 40 = 250 and
2x = 210 so
x = 105
Since Laura is x, she worked 105 hours in the lab and Doug worked 40 hours beyond what Laura worked. Doug worked 145. As long as those 2 numbers add up to 250, we did the job correctly. 105 + 145 = 250? I believe it does!!
Step-by-stm represents the number of months
Mike's: 30m
All-Day: 80 + 22m
30m = 80 + 22m and im pretty sure the answer is 102
The equation would be (x+4)+x=18. X stands for the amount of pears Wilma bought, and (x+4) is the amount of pears Tania bought (because she bought four more pounds than Wilma).
(X+4)+x=18
2x+4=18 (now you subtract four from both sides)
2x=14 (to get x by itself, divide both sides by 2)
X=7
Wilma bought 7 pounds of pears :3
In order to isolate k, we would first cross multiply
3*k=9*10
3k=90
Then to isolate k, we would divide both sides by 3 to get:
K=30
Hope this helps