Always start with what’s in the parentheses:)
The addition property of equality is the idea we can add some number to both sides of an equation. You must add the same number to both sides to keep things balanced.
It's asking "what number can we add to both sides of this equation so that we isolate x?"
Think of 20+x as x+20. We can rearrange terms since adding in any order doesn't matter (eg: 2+3 = 3+2 = 5)
So we really have this equation: x+20 = 25
We can add -20 to both sides to cancel out the +20 on the left side
x+20 = 25
x+20+(-20) = 25+(-20) ...... add -20 to both sides
x = 5
This is the exact same as subtracting 20 from both sides. So 5 will go where x is, meaning that 20+x = 20+5 = 25
The standard deviation is a measure of the variation of the data about the mean. So false.
Answer:
$ 850
Step-by-step explanation:
Martha and her brother started their own car-washing business.
We need to use front-end estimation to find out about how much their business will earn in 5 weeks.
Amount charged per car = $8.50
Number of cars washed per weekend = 22
Therefore, amount earned per weekend = Amount charged per car × Number of cars washed per weekend = 8.50 × 22 = $ 187
Amount earned in 5 weeks = amount earned per weekend × 5 = 187 × 5 = $ 935
Therefore, their business will earn $ 935 in 5 weeks.
