Systems of linear equations word problems — Basic example | Math | SAT | Khan Academy

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

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[eniskofte]

I think you solve the question long way. I have advice for answer method. İf you say ''Hazel'' has got x keys.Leo has x+4 of course.- 2x+4=18 x=7- and then you will find easily the answer.

[sofiaa]

I just solved this in my mind choose a random number for example 9 subtracting 4 and seeing if those two numbers gave me 18 took me less than a minute and I got 7

[Etren]

you could set the hazel and leo equal to each other at 9 and then subtract 2 from hazel’s number and add two to leo’s (9-2=7)(9+2=11)

[formagetounsi]

i remember this from primary school simply its H=(18-4)/2

[theyonko]

cant be a coincidence. hazel and leo?? like hazel and leo from heroes of olympus??? holyyy crap...