For this case, the first thing we must do is define variables.
We have then:
x: number of years
y: total salary
For company 1 we have:
For company 2 we have:
By the time both salaries are equal we have:
From here, we clear the value of x.
We have then:
Answer:
Brenda's salary would be the same with both companies in 8 years.
Answer: A
We could solve it but it's easier to just check the given solutions.
A. (7,1)
2y + 5 = 2(1)+5 = 7 = x, good
x/3-y = 7/3 - 1 = 4/3, good
B. (-3,8)
2y + 5 = 2(8)+5 = 21 not x=-3, doesn't check
C. Can't be true because we found a solution
D. Infinitely many solutions not true because the lines have different slopes
We have the following expression:
(6.34 x 10 ^ -7) (4.5 x 10 ^ 3)
The solution shown is:
(6.34 x 10 ^ -7) (4.5 x 10 ^ 3)
(6.34 x 4.5) (10 ^ -7 x 10 ^ 3)
28.53 x 10 ^ -4
-28.53 x 10 ^ 4
-2.853 x 10 ^ 3
The errors are:
A. He changed the sign of the coefficient. A negative exponent does not affect the sign of a coefficient in scientific notation. The sign of the exponent determines the direction the decimal is moved in.
D. He got the wrong value for the coefficients; 28.53 x 10^-4 is not possible. The coefficients in scientific notation are always greater than 1, but less than 10.
Answer:
Look at the attachment.
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Hope it helps ⚜
