Cracking The SAT Premium

In this case, the question is asking us to solve for y, so try to make the x terms disappear. You want to
make the coefficient of x zero, so you can quickly find the value of y. Here’s how:

Use the coefficient of x in the second equation, 5, to multiply the first equation:

5(3x    +   2y) =   5(17)

15 x    +   10y =   85

Then use the original coefficient of x in the first equation to multiply the second equation:

3(5x    −   4y) =   3(21)

15 x    −   12y =   63                      

Now stack your equations and subtract (or flip the signs and add, which is less likely to lead to a
mistake.)

Simplify your equation and you have your answer.

22 y    =   22

y   =   1

Solving Inequalities

In an equation, one side equals the other. In an inequality, one side does not equal the other. The following
symbols are used in inequalities:

≠ is    not equal   to

> is    greater than

< is    less    than

≥ is    greater than    or  equal   to; at  least

≤ is    less    than    or  equal   to; no  more    than

Hungry  Gator

Think   of  the inequality  sign

as  the mouth   of  a   hungry

alligator.  The alligator   eats

the bigger  number.

Solving inequalities is pretty similar to solving equations. You can collect like terms, and you can