Answer:
Solving systems of equations with 3 variables is very similar to how we solve systems with two variables. When we had two variables we reduced the system down
to one with only one variable (by substitution or addition). With three variables
we will reduce the system down to one with two variables (usually by addition),
which we can then solve by either addition or substitution.
To reduce from three variables down to two it is very important to keep the work
organized. We will use addition with two equations to eliminate one variable.
This new equation we will call (A). Then we will use a different pair of equations
and use addition to eliminate the same variable. This second new equation we
will call (B). Once we have done this we will have two equations (A) and (B)
with the same two variables that we can solve using either method. This is shown
in the following examples.
Example 1.
3x +2y − z = − 1
− 2x − 2y +3z = 5 We will eliminate y using two different pairs of equations
5x +2y − z = 3
Step-by-step explanation:
Answer:
Step-by-step explanation:
Let the total amount be x
Then Ali got 1/8x With 7/8x left
Juma got 7/40x with 7/10x left
Musa, Khalid and Mustafa got 7/30x each
since
7x=18000
Answer:
33.333
Step-by-step explanation:
Answer: Yes
Step-by-step explanation: bc 6(-3)+5=5(-3)+8+2(-3)
Becomes -18+5=-15+8+-6 which equals -13 on both sides meaning -3 is a solution
Answer:
A. 80-5x
Step-by-step explanation:
Let the number of rides be represented by = x
Thomas bought 80 tickets for rides at an amusement park. Each ride cost five tickets, Thomas has been on x right so far.
The number of rides Thomas has been on so far= 5 × x = 5x
The expressions to show the number of tickets that Thomas has left is written as:
80 - 5x
Option A is the correct option.