x + 7 = 2(3x - 4) Remove the brackets
x + 7 = 2*3x - 4*2
x + 7 = 6x - 8 Subtract 7 from both sides.
x + 7 - 7 = 6x - 8 - 7
x = 6x - 15 Subtract 6x from both sides
x - 6x = - 15
-5x = - 15 Divide by -5
-5x/-5 = -15/-5
x = 3
Answer:
-2
Step-by-step explanation:
find rise over run with y1-y2/x1-x2 = -2/1 = -2
8x+y=18
Y=3x-22
8x+3x-22=18
11x=40
X=40/11
Y=3×40/11-22
Y=-122/11
X=40/11
Y=-122/11
X+8y=17
X=y+8
Y+8+8y=17
9y=9
Y=1
X=1+8
X=9
Y=1
9x+y=58
Y=2x-8
9x+2x-8=58
11x=66
X=6
Y=2(6)-8
Y=12-8
Y=4
X=6
X+8y=21
X=2y+1
2y+1+8y=21
10y=20
Y=2
X=2 (2)+1
X=5
Y=2
Answer:
A: 82.5
Step-by-step explanation:
Average score of the 4 regular tests = (78 + 72 + 74 + 88)/4 = 78
We are told;
- the regular tests account for 40% of the final grade.
- final exam counts for 20%
- project counts for 10%
- homework counts for 30%
Thus;
weighted mean grade = (40% × 78) + (20% × 79) + (10% × 88) + (30% × 89) = 82.5
