Find the coordinates of the point of intersection of the lines 2x + 3y = 12 and y = 7 - 3x.

We can substitute the equation for y into 2x + 3y = 12.
If y = 7-3x , 2x + 3(7-3x) = 12 2x + 21-9x = 12
Now we can solve for x -7x = =-9x = 9/7
To get y, we must sub x back into y = 7 - 3x, to get the y co-ordinate.
y = 7-3(9/7) y = 7 - 27/7 y = 49/7 - 27/7 y = 22/7
(9/7, 22/7) is our intersection.

CA

Related Maths GCSE answers

All answers ▸

A sphere has a surface area of 4m^2, radius r. Another sphere has radius 2r. Calculate the Volume of the second sphere in M^3.


Prove that the square of an odd number is always one more than a multiple of 4


The equation of the line L1 is y = 3x – 2 The equation of the line L2 is 3y – 9x + 5 = 0 Show that these two lines are parallel


Rearrange the following making a the subject: (a+2)/5 = 3a+b