Answer:
(-4, -1)
Step-by-step explanation:
x = 4y
-4x - y = 17
Plug in 4y for x in the second equation:
-4(4y) - y = 17
Simplify. Remember to follow PEMDAS. Isolate the variable, y. Note the equal sign, what you do to one side, you do to the other.
First, multiply 4y with -4:
-4(4y) = -16y
-16y - y = 17
Simplify. Combine like terms:
-16y - y = 17
-17y = 17
Isolate the variable, y. Divide -17 from both sides:
(-17y)/-17 = (17)/-17
y = 17/-17
y = -1
Plug in -1 for y in the first equation:
x = 4y
x = 4(-1)
x = -4
x = -4, y = -1
Answer: (-4, -1)
~
Answer:
a) 6 2/5
b) 13 1/2
Step-by-step explanation:
Have a nice day!
Can I maybe have brainliest?
I forgot it was simplify..
First set up a proportion
240/160 = 320/200
Cross multiply and if the left equals the right it is similar.
The variance is the total of the squared distances of the given data from the mean.
This can be calculated through the equation,
σ² = summation of X² / N - μ²
where σ² is the variance X's are the data, N is the number of terms, and μ is the mean.
summation of X² = 100² + 100² + 120² + 120² + 180² = 81200
N = 5
μ = (100 + 100 + 120 + 120 + 180) / 5
μ = 124
Substituting these values to the equation for variance,
σ² = (81200/5) - 124² = 864
Thus, the variance is equal to 864.
