You’re answer will be “x=-2”
Answer: Option C) Raj forgot the negative when substituting -15+9x for y.
Solution:
(1) 9x-y=15
(2) 2x+8y=28
Isolating y in the first equation. Subtracting 9x both sides of the equation:
(1) 9x-y-9x=15-9x
Subtracting:
(1) -y=15-9x
Multiplying both sides of the equation by -1:
(1) (-1)(-y)=(-1)(15-9x)
(1) y=-15+9x
Then Raj found the value of y. It's not option D.
Substitutng y by -15+9x in the second equation:
(2) 2x+8(-15+9x)=28
Then option C) is the answer: Raj forgot the negative when substituting -15+9x for y.
Eliminating the parentheses applying the distributive property in the multiplication:
(2) 2x-120+72x=28
Adding similar terms:
(2) 74x-120=28
Solving for x. Adding 120 both sides of the equation:
(2) 74x-120+120=28+120
Adding:
(2) 74x=148
Dividing both sides of the equation by 74:
(2) 74x/74=148/74
Dividing:
(2) x=2
Solving for y: Replacing x by 2 in the first equation:
(1) y=-15+9x
(1) y=-15+9(2)
Multiplying:
(1) y=-15+18
Subtracting:
(1) y=3
11 cups of strawberries ... 6 pitchers of juice
x cups of strawberries = ? ... 1 pitcher of juice
If you would like to know what is the number of cups of strawberries in each pitcher, you can calculate this using the following steps:
11 * 1 = 6 * x
11 = 6 * x /6
x = 11/6
x = 1 5/6 cups of strawberries
Result: You will need 1 5/6 cups of strawberries in each pitcher.
Answer:
At 1% significance level, this difference is considered to be extremely statistically significant.
Step-by-step explanation:
Group Group One Group Two
Mean 41.300 54.800
SD 6.800 6.000
SEM 2.050 1.604
N 11 14
H0: Mean of group I = Mean of group II
Ha: Mean of group I < mean of group II
(Left tailed test at 1% significance level)
The mean of Group One minus Group Two equals -13.500
standard error of difference = 2.563
t = 5.2681
df = 23
p value= 0.00005
Since p < significance level, reject H0