B=books
Sold half of book: b/2
Bought six more: b/2+
Now has 12: b/2+6=12
Subtract 6 on both sides: b/2+6-6=12-6
b/2=6
Multiply both sides by 2: b=12
Answer= 12 books
Answer:
2/3 or 0.67
Step-by-step explanation:
Slope = y2 - y1 /x2 - x1
Given
x1 = 1
y1 = 8
x2 = 9
y2 = 12
Slope = 12 - 8 /9 - 1
= 4/6
Reduce is by 2
2/3
Or
0.67
x = number of 1-cent stamps
y = number of 8-cent stamps
z = number of 12-cent stamps
We have 31 stamps all together, so x+y+z = 31.
"I have 4 more 1-cent stamps than 8-cent stamps" means we have the equation x = y+8. Whatever y is, add 8 to it to get x. Solve for y to get y = x-8.
You also have "twice as many one cent stamps as 12 cent stamps", so x = 2z. Solving for z gets you z = 0.5x
-------------
x+y+z = 31
x+x-8+z = 31 ... y replaced with x-8
x+x-8+0.5x = 31 ... plug in z = 0.5x
2.5x-8 = 31
2.5x = 31+8
2.5x = 39
x = 39/2.5
x = 15.6
Your teacher made a typo somewhere because we should get a positive whole number result for x (since x is a count of how many 1-cent stamps we have).
Answer:
Multiply each measurement by 2 then add them together
OR
Add 7 + 3 and multiply by 2
Step-by-step explanation:
Answer would be 20ft
