Here are a few doubles facts:
5+5=10
2+2=4
3+3=6
A double is simply a pair of identical numbers added together. There's a pair of doubles you can <em>subtract </em>1 from to get 6+7, and there's a pair you can <em>add</em> 1 to get the same answer. What are those pairs?
Hint: If you take the example 3+4, you can either <em>subtract 1</em> from the double 4+4 or <em>add 1</em> to the double 3+3 to obtain your answer.
7h+3s=27.95 subtract 7h from both sides
3s=27.95-7h divide both sides by 3
s=(27.95-7h)/3
Then we are told:
5h+4s=23.4, using s found above makes this equation become:
5h+4(27.95-7h)/3=23.4 multiply both sides by 3
15h+4(27.95-7h=70.2 perform indicated multiplication on left side
15h+111.8-28h=70.2 combine like terms on left side
-13h+111.8=70.2 subtract 111.8 from both sides
-13h=-41.6 divide both sides by -13
h=$3.20
Answer:
D
Step-by-step explanation:
