Question 890743

pls help me to answer: the roots of quadratic equation x^2-7x+c differ by 1. find c.
<pre>
Let larger root be L
Then smaller root = L - 1
Sum of roots = L + L - 1, or 2L - 1
Also, sum of roots = {{{- b/a}}}, or {{{(- - 7)/1}}}, or 7
Therefore, 2L - 1 = 7
2L = 8
L, or larger root = {{{8/2}}}, or 4
Smaller root = 4 - 1, or 3

Product of roots = 4(3), or 12 
Also, product of roots = {{{c/a)
Therefore, {{{c/a = 12}}}, or {{{c/1 = 12}}}_______{{{highlight_green(highlight_green(c = 12))}}}