Math  /  Algebra

Questionems of Iline ar equations by 7. 8x7y=36x5y=1\begin{array}{l} 8 x-7 y=-3 \\ 6 x-5 y=-1 \end{array}

Studdy Solution

STEP 1

What is this asking? We've got two equations with two mystery numbers, xx and yy, and our mission is to find the *secret values* that make both equations true! Watch out! Keep your calculations neat and organized, a tiny mistake with a plus or minus sign can throw everything off!

STEP 2

1. Elimination Setup
2. Solve for xx
3. Solve for yy

STEP 3

Let's **multiply** the first equation by **5** and the second equation by **7**.
Why? Because we're setting the stage to *eliminate* yy!
This gives us: 5(8x7y)=5(3)5 \cdot (8x - 7y) = 5 \cdot (-3) 40x35y=1540x - 35y = -15and 7(6x5y)=7(1)7 \cdot (6x - 5y) = 7 \cdot (-1) 42x35y=742x - 35y = -7

STEP 4

Now, **subtract** the modified first equation from the modified second equation: (42x35y)(40x35y)=(7)(15)(42x - 35y) - (40x - 35y) = (-7) - (-15) 42x35y40x+35y=7+1542x - 35y - 40x + 35y = -7 + 152x=82x = 8

STEP 5

**Divide** both sides of 2x=82x = 8 by **2** to isolate xx: 2x2=82\frac{2x}{2} = \frac{8}{2} x=4x = 4We've found the first part of the puzzle! xx is **4**!

STEP 6

Let's **substitute** our shiny new value of x=4x = 4 back into the original first equation: 847y=38 \cdot 4 - 7y = -3 327y=332 - 7y = -3

STEP 7

**Subtract** 3232 from both sides: 327y32=33232 - 7y - 32 = -3 - 32 7y=35-7y = -35

STEP 8

**Divide** both sides by 7-7: 7y7=357\frac{-7y}{-7} = \frac{-35}{-7} y=5y = 5Boom! We've cracked the code! yy is **5**!

STEP 9

The solution to the system of equations is x=4x = 4 and y=5y = 5!

Was this helpful?

Studdy solves anything!

banner

Start learning now

Download Studdy AI Tutor now. Learn with ease and get all help you need to be successful at school.

ParentsInfluencer programContactPolicyTerms
TwitterInstagramFacebookTikTokDiscord