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## Digital SAT Math

### Course: Digital SAT Math>Unit 2

Lesson 6: Systems of linear equations word problems: foundations

# Systems of linear equations word problems — Basic example

Watch Sal work through a basic Systems of linear equations word problem.

## Want to join the conversation?

• hi, wont it be much easier if you just said:
Hazel amount of keys is X, Leo has 4 more keys, means X+4
and the both combined = 18:
X+4+X =18
2X = 18-4
2X=14\:2
X=7
and that's it.
• Bingo. That is also very quick 😉
• you could just do 18-4= 14/2=7
• i get how this works but, it's not something that comes to my mind. i've been thinking so hard why i would even think of doing 18-4 lol, like i get it but it's not intuitive and i'd not think of it in a problem...
• Do this:
9=9 (9+9=18)
divide 4 by 2, you get 2. (4 is the difference between the two values)
now add 2 to one side, and subtract 2 from the other.
9+2=9-2
11=7 (11+7=18)
Some of you guys will overthink something as simple as this, read the problem carefully and evaluate what you have learned one by one to successfully get the answer.
Please understand that I'm using the equal signs in a means to separate the two numbers, it holds no weight in this problem.
Good luck in the future!
-Sincerely from the man who will probably score a 600 on tomorrow's SAT.
• if L + H=18 take away 4 you get 14 leo=7 Hazel=7 then add the four back to Leo so Leo=11 Hazel=7
• what are equations to be precise?
• You mean the definition of equations?
"In mathematics, an equation is a statement that asserts the equality of two expressions."
• Ez pz !
• I did this:

L > H
L := H + 4 (L is bigger by H 4 more)

L + H = 18 total keys

(H+4) + H = 18
2H + 4 = 18
• cant you just do 18 minus 4 for this one?
• you'll have to divide 18 by 2 first, because 18 is the total keys.
so hazel and leo both get 9 keys each, but you want to add 4 to Leo's keys, because he has 4 extra. then you minus 4 from Hazel's keys.
(1 vote)
• The difference between in cost between a larger bag and a small bag of chips was \$1.48. We bought 6 large bags and 4 small bags and spent \$33.88. What was the cost of a small bag?
(1 vote)
• Let's say the smaller bag's cost is `s`
And the larger bag's cost is `s + 1.48` (because the difference is 1.48

6 large bags cost (6 times the price): 6(s + 1.48)
and 4 small bags cost (4 times the price): 4s
The sum of both costs is 33.88

Do you think you can continue the solution from where I left off?