9x - y = 15
2x + 8y = 28
Use the substitution method.
Solve for y in the first equation.
9x - y = 15
-y = 15 - 9x
y = -15 + 9x
Now plug in y into the second equation.
2x + 8(-15 + 9x) = 28
2x - 120 + 72x = 28
74x - 120 = 28
74x = 148
x = 2
Plug x back into the rewritten first equation.
y = -15 + 9(2)
y = -15 + 18
y = 3
x = 2, y = 3
In order to answer the question we need a picture of some kind
Answer:
![[p-|p|*10^{-3} \, , \, p+|p|* 10^-3]](https://tex.z-dn.net/?f=%5Bp-%7Cp%7C%2A10%5E%7B-3%7D%20%5C%2C%20%2C%20%5C%2C%20p%2B%7Cp%7C%2A%2010%5E-3%5D)
Step-by-step explanation
The relative error is the absolute error divided by the absolute value of p. for an approximation p*, the relative error is
r = |p*-p|/|p|
we want r to be at most 10⁻³, thus
|p*-p|/|p| ≤ 10⁻³
|p*-p| ≤ |p|* 10⁻³
therefore, p*-p should lie in the interval [ - |p| * 10⁻³ , |p| * 10⁻³ ], and as a consecuence, p* should be in the interval [p - |p| * 10⁻³ , p + |p| * 10⁻³ ]
450000 * .08
= 36,000
They reduce $36,000 from the original price.