Bob needs to save at least 10 dollars to buy that book
he gets 2 dollars in allowance every day
he has 3 dollars now
in how many days will he be able to buy the book?
translation
if d=number of days
then
how much has now+how much will earn≥10
3+2d≥10
solve
minus 3 both sides
2d≥7
divide both sides by 2
d≥3.5
but wait, you can't have 3.5 days, round up becuase if round down you wil have less than $10
answer is 4 days
that is an example, just read it and don't just report it
Answer:
hold up lemma check
Step-by-step explanation:
2l+2w=24
l=3+w
The first equation comes from the perimeter formula. Since it is a rectangle, there are two lengths and two widths, which must all be added to get the perimeter. The second equation shows that the length is equal to the width plus three. In order to solve this equation, the substitution method should be used, since the one equation is already set equal to one of the variables (L)
2l+2w=24
l=3+w
2(3+w)+2w=24
Use distributive property to get rid of the parentheses
2(3+w)+2w=24
2(3)+2(w)+2w=24
6+2w+2w=24
Simplify like terms on the left side of the equation
6+2w+2w=24
6+4w=24
Subtract six from each side so that all of the w's are on one side
6+4w-6=24-6
4w=18
Divide each side by four to find the value of one w
4w/4=18/4
w=4.5
Plug 4.5 into the one equation to find the value of l
l=3+4.5
l=7.5
Put the numbers into the first equation and simplify:
2(7.5)+2(4.5)=24
15+9=24
24=24
So the length would be 7.5 inches, and the width would be 4.5 inches
<span><u>8x + 9 = 5x + 18</u>
Subtract 9 from each side:
8x = 5x + 9
Subtract 5x from each side:
3x = 9
Divide each side by 3 :
<u>x = 3</u>
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