Algebra

accuracy vs precision
algebra
significant figures
statistics
system international (SI)
trig

Solve each of the following for x. You can do half of them, but these are important.

1) 20 + 4X = 6 - 3X

2) 140 - 2X = –- 6 (3X –- 10)

3) 4 = 12/(3X + 6)

4) X0.5 + 24 = 30

5) 5X = 15/(X + 2)

When you have 2 equations and two unknowns you have several options to solve for the variables.

  1. linear combination
  2. substitution
  3. graphing
  4. matrices

Use the example 2X + Y = 1 and 3X - 2Y = 26 .

Linear combination would have you multiply the first equation by 2 and then add the two equations so that you end with 7X = 28 to get the value of X.

Substitution would have you solve the first equation for Y and then substitute that into the second equation. Again you should get 7X = 28.

Use the TI calculator to graph both equations and zoom in to get the coordinates of the intersection point.

Matrices is an additional option.

Do each of the problems with three methods described above.

1) 3X + 2Y = -2     X - 3Y = 25

2) 4X + 3Y = 4     3X – Y = -10

last modified 5-30-10