Y=3x-4
4x-5y=-13
4x-5(3x-4)=-13
4x-15x+20=-13
-11x+20=-13
33=11x
x=3
y=3(3)-4
y=9-4
y=5
First the number of ways of selecting 3 students out of 8 is 8*7*6/(3*2*1)=56.
There are 6 ways of arranging the officers, so the total number of ways is 6*56=336
Answer:
➳ These equations will have <u>infinite solutions</u> because they are in 2 variables. Any value can be substituted in the place of the variables x & y.
I one is 8x<24 and -8≤2x-4
Hence x <24/8 =3 and -4≤2x: divide by positive 2 to get -2≤x
Hence solution is -2≤x<3
Therefore c is the correct matching for 1.
2) 5x-2>13 or -4x≥8
i.e. 5x>15 or x≤8/(-4) = -2 (since dividing by negative inequality reverses)
Or x>3 or x ≤-2
Hence solution is two regions to the right of 3 excluding 3 and left of -2 including -2.
Graph b is the correct match.
3) -25≤9x+2<20
Subtract 2
-27≤9x<18: Now divide by positive 9
-3≤x<2
Hence graph is the region between -3 and 2 including only -3.
Graph a is correct matching for question 3.
- 8x + 44 ≥ 60
- 8x ≥ 60 - 44
- 8x ≥ 16
x ≤ - 2
- 4x + 50 < 58
- 4x < 58 - 50
- 4x < 8
x > - 2
Now put the two together. Logically, these two answers since a number cannot be both less than AND greater than - 2.
Your answer should be no solution.
