Answer:
A and C
Step-by-step explanation:
-3*3 = -9
-1*-9 = 9
-27/3 = -9
-9/-1 = 9
Let
R = Ralph's age
S = Sara's age
First statement is translated as:
S = 3R
Second statement is translated as:
S + 4 = 2(R + 4)
Use the first equation to be substituted into the second one in terms of R which is the one we are actually going to solve for Ralph's age.
Since S = 3R, then
3R + 4 = 2(R + 4)
3R + 4 = 2R + 8
3R - 2R = 8 - 4
R = 4 years old
You need another equation, other wise x can be anything, and y can be infinitely different solutions.
The equation you can use to relate L to D uses the information in the first part of the problem. First, if we just add 4 miles every day (ignoring the other piece), the length of the road would be 4 times the number of days, or L = 4D. But since we started with 57 miles built, we have to add that in order to get the total length, so the equation would be:
L = 4D + 57
You can use this question to find any value of L or D if you know one of them. According to the questoin, we know the crew worked 34 days (or D). So if you plug in 34 for D you'll get:
L = 4(34) + 57 ->
L = 136 + 57 ->
L = 193
