59 is an outlier it's not in the 70s
Try breaking these into sections.
Twice: 2 times
The sum of: add
A number: choose a variable, like x
---Thus "the sum of a number and 4" becomes "add x and 4" which, mathematically, is "x+4"
-----Continuing to put it all together, "Twice the sum of a number and four" becomes "2 times (x+4)" which, mathematically, is "2(x+4)"
Is: equals
-------"Twice the sum of a number and four is" becomes "2(x+4)="
23 less than: subtract 23. This one tends to trick people; "23 less than" will become "__ - 23", NOT "23 - __"
three times the number: 3 times x
---"23 less than three times the number" becomes "subtract 23 from 3 times x" which, mathematically, is "3x-23"
-------So the final phrase: 2(x+4)=3x-23"
Answer:
Since there is one value of y for every value of x in (−4,8),(−2,4),(0,1),(2,4), ( 4,8), this relation is a function. The relation is a function.
Step 1: Divide both sides by x.<span><span><span>fx</span>x</span>=<span><span><span>−<span>4.5x</span></span>+7</span>x</span></span><span>f=<span><span><span>−<span>4.5x</span></span>+7</span>x</span></span>Answer:f=<span><span><span>−<span>4.5x</span></span>+7</span><span>x</span></span>
You do the following.
Take the price of the most expensive subscription and retract the price of the cheap one.
$50-$40 = $10
Since we know what the price of a text message and the difference in dollars between the two subscriptions, we can calculate how many text messages has to be sent. We just divide the result from before ($10) with the price of a text message ($0.2)
$10/$0.2 = 50
The total number of text messages that needs to be send in order for the price of the subscriptions to be the same, is 50.