Solve the following system:
{3 x - 5 y = 7 | (equation 1)
{10 y - 4 x = 16 | (equation 2)
Swap equation 1 with equation 2:
{-(4 x) + 10 y = 16 | (equation 1)
{3 x - 5 y = 7 | (equation 2)
Add 3/4 × (equation 1) to equation 2:
{-(4 x) + 10 y = 16 | (equation 1)
{0 x+(5 y)/2 = 19 | (equation 2)
Divide equation 1 by 2:
{-(2 x) + 5 y = 8 | (equation 1)
{0 x+(5 y)/2 = 19 | (equation 2)
Multiply equation 2 by 2:
{-(2 x) + 5 y = 8 | (equation 1)
{0 x+5 y = 38 | (equation 2)
Divide equation 2 by 5:
{-(2 x) + 5 y = 8 | (equation 1)
{0 x+y = 38/5 | (equation 2)
Subtract 5 × (equation 2) from equation 1:
{-(2 x)+0 y = -30 | (equation 1)
{0 x+y = 38/5 | (equation 2)
Divide equation 1 by -2:
{x+0 y = 15 | (equation 1)
{0 x+y = 38/5 | (equation 2)
Collect results:
Answer: {x = 15
{y = 38/5 or 7.6 decimal
Answer:
Eudora ran for 30 minutes and use the jetpack for 1 hour and 30 minutes
Step-by-step explanation:
Lets call x the time she ran and y the time she was using a jetpack (in hours), we have
12x + 76y = 120
Since it took 2 hours we have that x+y = 2, hence y = 2-x. We can replace y in the equation above, obtaining
12x + 76(2-x) = 120
12x+ 152 - 76x = 120
12x-76x = 120-152
-64x = -32
x = -32/-64 = 1/2 (30 minutes)
As a result
y = 1-1/2 = 3/2 (1 hour, 30 minutes)
She ran for 30 minutes and use the jetpack for 1 hour and 30 minutes.
Answer:
C. The difference of the two means is not significant, so the null hypothesis must be rejected
Step-by-step explanation:
According to the Question,
Given, The difference of sample means of two populations is 55.4, and the standard deviation of the difference of sample means is 28.1 .
Now, if we are testing the null hypothesis at the 95% confidence level .
- Thus, the difference of the two means is not significant at the 95% confidence level, so the null hypothesis must be rejected .
Answer:
It's Ok
Step-by-step explanation:
Mark me brainliest :>
Answer:
12 dozen
Step-by-step explanation:
create a proportion of: dozen cookies / cups of pecan
let 'd' = dozen cookies
(3/1 ÷ 5/4) = (d ÷ 5)
simplify 3/1 ÷ 5/4 to be: 3/1 x 4/5, which equals 12/5
12/5 = d/5
cross-multiply to get:
5d = 60
d = 12