Answer:
Step 1 and step 2
Step-by-step explanation:
she has to subtract 30 not add 30.
2(3x+6)=3(x-10)
6x + 12 = 3x-30
6x +12 - 12 = 3x - 30 - 12
6x = 3x - 42
6x - 3x = 3x - 42 - 3x
3x = -42
3x/3 = -42/3
x = -14
Ok so this all about subtracting fractions this is what you want to do:
you can change 8 3/4 and 4 2/3 to have the same value and deominator
8 3/4 = 8 9/12(multiply both sides by 3)
4 2/3 = 4 8/12(multiply both sides by 4)
you do this because 12 is divisible by 3 and 4
then, subtract 4 8/12 from 8 9/12 because John is using some of the wood his dad gave him.
then subtract once again, taking 11/2 away from your difference.
again match the deominator of 11/2 to the deominator of your difference which should be 12. another divisible of 12 is 2 and 6.
11/2 = 66/12 = 5 6/12(multiply both the top and bottom by 6)
and start subtracting.
so John should have -1 5/12(?) wood left
You have the ratio set up correctly:
2x+2/12 = x+3/21
Now cross multiply:
2x+2 * 12 = x+3 * 21
Simplify:
24x + 24 = 21x + 63
Subtract 24 from each side:
24x = 21x + 39
Subtract 21x from each side:
3x = 39
Divide both sides by 3:
x = 39/3
x = 13
Set up a proportion:
3.9/11.7 = 13.2/x
Cross multiply:
3.9x = 154.44
Divide 3.9 to both sides:
x = 39.6
So the shadow for an object that is 13.2 will be 39.6 feet long.
