x-y=21 ⇒ x=y+21
x+13=2y
Substitute y+21 for x into the equation x+13=2y
So y+21+13=2y
Simplify 34=y
So Danielle is 34 years old. Plug y back in to the original equation
x-34=21
x=55
Tony is 55 years old
3x = -6y + 6 becomes x = -2y + 2 and then you substitute in 5( -2y + 2) + 4y = -14
-10y + 10 + 4y = -14
-6y = -24
6y = 24
y = 4
And then you put y in x = -2(4) + 2 to find x
X = -8 + 2 = -6
x = -6
Then you try in both
5(-6) + 4(4) = - 14 -> -30 + 16 is -14 ✔️
3(-6) + 6(4) = 6 -> -18 + 24 is 6 ✔️
0.4 because if it’s five or more, add one more. If it’s four or less, let it rest.
The point estimate of the mean of the sample is (<span>39 + 31 + 38 + 40 + 29 + 32 + 33 + 39 + 35 + 32 + 32 + 27 + 30 + 31 + 27 + 30 + 29 + 34 + 36 + 25 + 30 + 32 + 38 + 35 + 40 + 29 + 32 + 31 + 26 + 26 + 32 + 26 + 30 + 40 + 32 + 39 + 37 + 25 + 29 + 34) / 40 = </span>1292/40 = 32.30
The point proportion of defective units is 2/40 = 0.05
Hope these notes help ! https://mathbitsnotebook.com/Algebra1/Quadratics/QDVertexForm.html
