Answer:
Different ways to solve a system of linear equations:
- isolate one variable in one equation and replace it in the other equation
- multiply/divide one equation by a constant and then add/subtract it to the other one, so that only one variable remains
- graph the equation and look at the intersection point
If you graph the system:
- there is only one solution if the lines intersects at only one point
- there is no solution if the lines don't intersect each other (they are parallel)
- there are infinitely many solutions if the lines overlap each other (they are the same equation multiplied by some constant)
Step-by-step explanation:
1st system
y = -x – 7
y = 4/3 x – 7
solution: x= 0, y = 7
2nd system
y = -3x – 5
y = x + 3
solution: x = -2, y = 1
3rd system
y = -2x + 5
y = 1/3 x – 2
solution: x = 3, y = -1
4th system
3x + 2y = 2
x + 2y = -2
solution: x = 2, y = -2
5th system
x + 3y = -9
2x – y = -4
solution: x = -3, y = -2
6th system
x – 2y = 2
-x + 4y = -8
solution: x = -4, y = -3
7th system
5x + y = -2
x + y = 2
solution: x = -1, y = -3
22 students...16 boys
probability student will be a boy is 16/22 which reduces to 8/11 or 72.7%
40×4×4=640
b=20 h=4
using formula:
1/2×base×height
1/2×20×4=40
its says scale by factor 4:
b=80 h=16
using formula:
1/2×base×height
1/2×80×16=640
answer------>>>>640cm^2
N= 66°
k= 29°
All triangles add up to 180 so that’s how i got those
Answer: d=5
Step-by-step explanation:
Arithmetic progression
An=a1+d(n-1)
An= nth term
A1= first term
D= common difference
N= nth position
We are given the 4th and 7th terms
For 4th term,n=4
A4=a1+d(4-1)
A4= 16
16= a1+d(4-1)
16= a1+3d........equation 1
For the 7th term,n=7
A7=a1+d(7-1)
A7= 31
31=a1+6d......equation 2
Bring them together
16=a1+3d
31=a1+6d
Subtract equation 1 from 2
So we have
15=3d
D=15/3
D=5
Therefore, the common difference is 5