the step by step instructions r in the pics
Answer:
solution is (- 3, 5 )
Step-by-step explanation:
given the 2 equations
6x - y = - 23 → (1)
8x + 3y = - 9 → (2)
rearrange (1) expressing y in terms of x
y = 6x + 23 → (3)
Substitute y = 6x + 23 into (2)
8x + 3(6x + 23 ) = - 9
8x + 18x + 69 = - 9
26x + 69 = - 9 ( subtract 69 from both sides )
26x = - 78 ( divide both sides by 26 )
x = - 3
substitute x = - 3 into (3)
y = (6 × - 3 ) + 23 = - 18 + 23 = 5
solution is (- 3, 5 )
Answer:
Step-by-step explanation:
14) 2x - 10 = 80 {alternate interior angles are equal}
2x = 80 + 10
2x = 90
x = 90/2
x = 45°
15) 3x + 120 = 180 { co interior angles are supplementary}
3x = 180 - 120
3x = 60
x = 60/3
x = 20°
16) 3x + 15 = 135 {corresponding angles are equal}
3x = 165 - 15
3x = 150
x = 150/3
x = 50°
Answer:
What is the sample variance of bottle weight 2.33
Step-by-step explanation:
First find the mean. The mean of the bottle weight is obtained by taking the ratio of the sum of ages and total number of ages.
Mean = (4+2+5+4+5+2+6) / 7
= 28 / 7
= 4
Sample Variance = ![\frac{\left[\begin{array}{ccc}(4-4)^{2} +(2-4)^{2} +\\(5-4)^{2} + (4-4)^{2} +\\(5-4)^{2} + (2-4)^{2} +\\(6-4)^{2}\end{array}\right]}{7-1}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%284-4%29%5E%7B2%7D%20%2B%282-4%29%5E%7B2%7D%20%2B%5C%5C%285-4%29%5E%7B2%7D%20%2B%20%284-4%29%5E%7B2%7D%20%2B%5C%5C%285-4%29%5E%7B2%7D%20%2B%20%282-4%29%5E%7B2%7D%20%2B%5C%5C%286-4%29%5E%7B2%7D%5Cend%7Barray%7D%5Cright%5D%7D%7B7-1%7D)
=
= 2.33