Show that the lines y=3x+7 and 2y-6x=8 are parallel (not using a graphical method).

The standard form of a straight line is y = mx + c, where y and x are variables that depend on each other, m is the gradient and c is the y-axis intercept. An important fact for this question is that parallel lines have the same gradient.We see the first line is already in the standard form of a line and we can see from inspection that the gradient of y = 3x + 7 is 3.We now seek to get the second line in the same form. By adding 6x to both sides we see that 2y = 6x + 8.Now simply dividing by 2 on both sides we get y = 3x + 4 and we can see that the gradient of this line is also 3Hence the lines are parallel.

MB

Related Maths GCSE answers

All answers ▸

Show that (x + 1)(x + 2)(x + 3) can be written in the form ax3 + bx2 + cx + d where a, b, c and d are positive integers.


Examine the sequence 1 + 1/3 + (1/3)^2 + … + (1/3)^n Under what condition does it converge? What does it converge to?


Expand and simplify (x+5)(x+7)


What is differentiation and what does it actually mean?