Answer:
6. 6x-21=33+9x 7. -15x=-5(3x+7) 8. 16x-19=113-6x 9. -19x-34=56-x 10. -6(4x+3)=6(4x-3)?
6. 6x-21 = 33 +9x
+21 + 21
6x = 54 + 9x
-9x -9x
-3x = 54
/3 /3
x = -18
7. -15x = -5(3x+7)
First multiply the -5 to the other numbers.
-15x = -15x - 35
0x = -35
7 is impossible I believe.
8. 16x-19 = 113-6x
+6 +6
22x - 19 = 113
+ 19 +19
22x = 132
/22 /22
x = 6
9. -19x - 34 = 56 - x
+19x +19x
-34 = 56 + 18x
-56 -56
-90 = 18x
/18 /18
x = -5
10. -6(4x+3) = 6[4x-3]
-24x - 18 = 24x - 18
+18 +18
-24x= 24x
x = 0, since only zero can make the equation true.
Step-by-step explanation:
Distance = rate × time
If b is the speed of the boat in still water, and c is the speed of the current, then:
60 = (b + c) × 4
35 = (b − c) × 3.5
Simplifying:
15 = b + c
10 = b − c
Add the equations together:
25 = 2b
b = 12.5
Plug into either equation to find c:
c = 2.5
The speed of the boat is 12.5 km/h, and the speed of the current is 2.5 km/h.
Answer:
4. -2s^9
7. 8b^10
Step-by-step explanation:
First, focus on the number part of the expression. For 4), multiply -2 x -1 x -1 = -2. Then, look at the exponents. When you're multiplying exponents with the same base (in number 4, the base is s), you can add the exponents.
2+3+4 = 9; which makes it s^9. Multiply -2 x s^9, which gives you -2s^9.
Same thing for 7). Multiply all the numbers first. this gives you 8. (Remember two negatives equals a positive). Add all of the exponents of b together, which gives you 10. (when a variable has no exponent, it means that the exponent is 1.) Multiplying 8 and b^10 should give you 8b^10.
It may help to brush up on exponent rules and sign rules.
Answer:
full arrow going left from 46
Step-by-step explanation:
See the attached picture.
Answer could change slightly depending on how all the steps are rounded.