x = -9
-3x when x is 3 would be -3(3) = -9
Answer:
Step-by-step explanation:
12.9 + 10.2x = 35.1
10.2x = 35.1 - 12.9
10.2x = 22.2
x = 22.2/10.2
x= 222/102 = 111/51
Answer:
x=9
Step-by-step explanation:
We can use similar triangles and ratios. Put the small triangle side over the large triangle side.
9cm 3x -20
---------- = ---------------- We need to add the sides to get to the larger triangle
72+9 cm 3x-20 + 56
We can cross multiply to solve
9 * (3x-20+56) = (72+9) * (3x-20)
Simplify
9*(3x+36) = 81*(3x-20)
Distribute
27x +324 = 243x -1620
Subtract 27x from each side
27x-27x +324 = 243x-27x -1620
324 = 216x-1620
Add 1620 to each side
324+1620 = 216x
1944 = 216x
Divide each side by 216
1944/216 = 216x/216
9=x
Total people in the cafeteria = 7 + 48 + 45 = 100
There are 45 boys.
The probability would be the number of boys over the total number of people:
45/100, which simplifies to 9/20
Answer:
12 girls
Step-by-step explanation:
multiply 8 by 3/2 to get 12.
