164k views
3 votes
If x= 4y + 3 and y = -2x - 3, what is the value of xy?

2 Answers

6 votes

Given that :-

  • x = 4y +3

  • y = -2x -3

To Find :-

  • Value of x.y

Solution :-

→ x = 4y + 3 equation 1st

→ y = -2x -3 equation 2nd .

Now putting the value of x from first equation to second equation.

→ y = -2(4y +3 ) -3

→ y = -8y - 6 - 3

→ y + 8y = -9

→ 9y = -9

y = -1

Now putting the value of y in equation first .

→ x = 4(-1) + 3

→ x = -4 + 3

x = -1

Now multiply and X and y.

→ x.y = -1(-1)

x.y = 1 .

User Laurens Koppenol
by
8.3k points
6 votes


\huge {\bold {\star {\fcolorbox {black} {yellow} {Answer}}}}

Given,

  • x = 4y + 3 ⠀⠀⠀⠀⠀⠀ i
  • y = -2x - 3⠀⠀⠀⠀⠀⠀⠀⠀ii

To find;

  • The value of xy


{\boxed{\red{\underline{\sf{Solution:}}}}}

Putting the value of x in ii, we get ;

➝ y = - 2(4y+3) - 3

➝ y = - 8y - 6 - 3

➝ y = - 8y - 9

➝ y + 8y = - 9

➝ 9y = - 9

∴ y = - 1

Putting the value of y in i, we get ;

➝ x = 4y + 3

➝ x = 4(-1) + 3

➝ x = - 4 + 3

∴ x = - 1

Now,

➛ xy = (- 1)(-1)

⛬ xy = 1

User AShah
by
7.9k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories