Answer:
see explanation
Step-by-step explanation:
Given the 2 equations
5x + y = 21 → (1)
x - 3y = 9 → (2)
Multiply (1) by 3 and add the result to (2) to eliminate y term
15x + 3y = 63 → (3)
Add (2) and (3) term by term
(x + 15x) + )- 3y + 3y) = (9 + 63)
16x = 72 ( divide both sides by 16 )
x = 4.5
Substitute x = 4.5 into (1) for corresponding value of y
22.5 + y = 21 ( subtract 22.5 from both sides )
y = - 1.5
Solution is (4.5, - 1.5 )
Answer:
Step-by-step explanation:
We can easily find the determinant of a matrix of which will be the cofactor of 2. Multiplying the diagonal elements of the matrix, we get. Now subtract the value of the second diagonal from the first, i.e, 48 – 3 = 45. Check the sign that is assigned to the number
You forgot to include the given line.
We need the given line to find the slope. The slope of parallel lines are equal. So, the slope of the line of the equation you are looking for is the same slope of the given line.
I can explain you the procedure to help you to find the desired equation:
1) Slope
Remember that the slope-intercept equation form is y = mx + b where m is the slope and b is thye y-intercept.
If you clear y in every equation you get:
a) y = (3/4)x + 17/4 => slope = 3/4
b) y = (3/4)x + 20/4 = (3/4)x + 5 => slope = 3/4
c) y = -(4/3)x - 2/3 => slope = -4/3
d) y = (-4/3)x - 6/3 = (-4/3)x - 2 => slope = -4/3
So, you just have to compare the slope of the given line with the above slopes to see which equations are candidates.
2) Point (-3,2)
You must verify which equations pass through the point (-3,2).
a) 3x - 4y = - 17
3(-3) - 4(2) = -17
- 9 - 8 = - 17
- 17 = - 17 => it is candidate
b) 3x - 4y = - 20
- 17 ≠ - 20 => it is not candidate
c) 4x + 3y = - 2
4(-3) + 3(2) = - 2
-12 + 6 = - 2
-6 ≠ -2 => it is not candidate
d) 4x + 3y = - 6
-6 = - 6 => it is candidate
3) So, the point (-3,2) permits to select two candidates
3x - 4y = - 17, and 4x + 3y = -6.
4) Yet you have to find the slope of the given equation, if it is 3/4 the solutions is the equation 3x - 4y = -17; if it is -4/3 the solution is the equation 4x + 3y = -6.
8weeks
10% of 200 is 20if you subtract 20 from 200 then you have to do it 8 times to get below 50
#1) 200-20=180
#2) 180-20=160
#3) 160-20=140
#4) 140-20=120
#5) 120-20=100
#6) 100-20=80
#7) 80-20=60
#8) 60-20=40
