Question 334559: how do you make "three more than the sum of a number and four" into and algebraic expressiom? Found 2 solutions by Fombitz, Edwin McCravy:Answer by Fombitz(32388) (Show Source):
You can put this solution on YOUR website! Choose a variable, say Z, as the unknown number.
The sum of Z and 4 is .
Three times the sum of Z and 4 would be
[The other tutor apparently was in a hurry and mistakenly read your
"more than" as "times"]
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"three more than the sum of a number and four"
Change the red words "a number" to a letter of your choice, say, x, and we have:
"three more than the sum of x and four".
Next change the blue words the sum of x and four" in:
"three more than the sum of x and four".
to (x + 4)
"three more than (x + 4)".
Now we see that the green words "three more than"
"three more than (x + 4)".
are on the LEFT in English. However, in algebra, to make something 'more',
we think of starting with the thing we are going to 'make more' and
then make it more by adding to it on the RIGHT. So we not only switch the
blue words to "+ 3, but we also put it on the
RIGHT side. So we end up with
(x + 4) + 3
Now you can simplify that by removing parentheses:
x + 4 + 3
and end up by adding the two number terms, getting
x + 7.
However your teacher may have wanted you to leave it unsimplified as
(x + 4) + 3.
Edwin
