Use The Linear Combination Method To Solve The System Of Equations. Explain Each Step Of Your Solution. If Steps Are Not Explained, You Will Not Recei

Use the linear combination method to solve the system of equations. Explain each step of your solution. If steps are not explained, you will not receive credit for that step.

2x+9y= -26
-3x-7y=13

  Answer:

x = 5
y = -4

Explanation:

2x + 9y = -26
-3x - 7y = 13
___________

One of the variables should be cancelled
For that to happen the signs should be different and when you add it they will be cancelled
If you cant cancel any of them then you have to think what to MULTIPLY or what you should do to the equations

First, pick one of the variables that you want to cancel
So i want to cancel "x"
For that to happen i should think what to multiply to the equations for them to be cancelled
Im going to multiply them by 3 and 2

3(2x + 9y = -26)
2(-3x - 7y = 13)
___________

Then distribute them

6x + 27y = -78
-6x - 14y = 26
____________

You can cancel the "x" now and then add them

13y = -52

Divide 13 from both sides

13/13y = -52/13

Solve

y = -4

After getting the value of one of the variables substitute it to one of the equations to get the value of the other variable (you can choose any equation between the two of them)

2x + 9y = -26
2x + 9(-4) = - 26
2x - 36 = -26
Transpose - 36 and then change the sign
2x = -26 + 36
Compute them
2x = 10
Divide 2 from both sides
2/2x = 10/2
Solve
x = 5

_____CHECKING_____
2x + 9y = -26
2(5) + 9(-4) = -26
10 - 36 = -26
-26 = -26 TRUE

-3x - 7y = 13
-3(5) - 7(-4) = 13
-15 + 28 = 13
13 = 13 TRUE

Comments

Post a Comment

Popular posts from this blog

1.)Jay Drops A Stone From Rest At The Top Of 55m Tall Building.With What Velocity Does It Hit The Ground?, 2.) A Ball Drops Freely From The Roof Towar

1.)Jay Drops a stone from rest at the top of 55m tall building.With what Velocity does it hit the ground? 2.) A ball drops freely from the roof towards the ground . What is the distance of the roof from the ground if the time lapsed when the ball hits the ground is 8 seconds? 3.) If a ball falls, From the roof top of a building towards the ground in 10s, How tall is the building? Sana may tumulong... Wlaa talaga akong idea sa science ih   In kinematics, there are 4 MOST COMMON KINEMATIC FORMULAS we use to solve the problems. These are 1. d = (Vi)(t) + (1/2)(a)(t^2) 2. Vf = Vi + at 3. (Vf)^2 = (Vi)^2 + 2ad 4. d = ((Vi +Vf)/2)(t) But when do we really use them in solving the problems? Let us first identify the variables involved in the equations. The first variable "d" is the distance that the certain object in motion reaches after a certain amount of time (t). Vf and Vi are what we call the FINAL AND INITIAL VELOCITIES of the object. Why there is final
Read more

What Is The Definition Of Social Justice?

What is the definition of social justice?   Social justice is a concept of fair and just relations between the individual and society. This is measured by the explicit and tacit terms for the distribution of wealth, opportunities for personal activity, and social privileges.
Read more

A Companys Fixed Cost Is 120000. It Cost The Company 280 To Prduce Each Unit Of Its Product And It Sells Each Unit For 310

Image
a companys fixed cost is 120000. It cost the company 280 to prduce each unit of its product and it sells each unit for 310   Answer: If you are asking about the amount of product units that must be sold to break-even, then the answer is 4000 units .   Step-by-step explanation: This is a type of economics problem. The formula relating the profit P , Variable costs VC , Fixed Costs FC ,  Product Demand D , and Selling Price p is shown below:     (Eqn 1) In order to get the breakeven demand, we must first define what breakeven means. Breakeven point is a point that forms from the intersection of  supply and demand curves. In simple words, it is the certain event where your profit is basically equal to 0 . But what is Breakeven Demand? Breakeven Demand is the number of product units that must be sold in order to get the breakeven point. Thus, we can use Eqn 1 to derive the formula in finding the breakeven demand.   (Eqn 2) Using this equation we can now find the breakeven deman
Read more