Answer: There are 69 adults and 72 children went to the concert.
Step-by-step explanation:
Let x be the number of adults, and y be the number of children.
x + y = 141
3.5x + 2.5y = 421.5
x + y =141
x = 141 - y
3.5(141 - y) + 2.5y = 421.5
493.5 - 3.5y + 2.5y = 421.5
493.5 - y = 421.5
-y = -72
y = 72
x + y = 141
x + 72 = 141
x = 69
Answer:
Option 3 - 
Step-by-step explanation:
Given : Perpendicular to the line
; containing the point (4,4).
To Find : An equation for the line with the given properties ?
Solution :
We know that,
When two lines are perpendicular then slope of one equation is negative reciprocal of another equation.
Slope of the equation 
Converting into slope form
,
Where m is the slope.


The slope of the equation is 
The slope of the perpendicular equation is 
The required slope is 

The required equation is 
Substitute point (x,y)=(4,4)



Substitute back in equation,

Therefore, The required equation for the line is 
So, Option 3 is correct.
Answer:
Option D
Step-by-step explanation:
We are given the following equations -

It would be best to solve this equation in matrix form. Write down the coefficients of each terms, and reduce to " row echelon form " -
First, I swapped the first and third rows.
Leading coefficient of row 2 canceled.
The start value of row 3 was canceled.
Matrix rows 2 and 3 were swapped.
Leading coefficient in row 3 was canceled.

And at this point, I came to the conclusion that this system of equations had no solutions, considering it reduced to this -

The positioning of the zeros indicated that there was no solution!
<u><em>Hope that helps!</em></u>
2K + 5 = 29
(2 x K) + 5 = 29
29 - 5 = 24
24 divided by 2 = 12 (This is K)
K = 12
(2 x 12) + 5 = 29
24 + 5 = 29