This is frustrating!
The diagram at the right demonstrates the idea of rectangular numbers.
the formula N=w(w+1) give the values of a rectangular based on a shape with a width of w dots.
a.) which rectangular number has a width of 6?
the diagrams at right are
w=1 w=2 w=3
N=1 N=6 N=12
This is my thought process and maybe someone can tell help think a little better?
So i haven't learnt the quadratic formula yet nor has the book covered it yet, so i can only worry about what the book has taught me! They've given a formula and the question asks which rectangular number has a width of 6. So its asking for N, theres a formula for that which they give, so don't i plug 6, which is what they're basically saying what is N when the rectangular number has a width of 6, so i plug 6 into the formula. So the formula is N=w(w+1) so w(w+1)=N which is what we're trying to find right?
n=36w^2+6w, now i look at that and say how can i solve for W, well i need a constant don't i? So i can use the null factor law, which basically solves for x… in this case w. So i need a constant how can i get that constant?
Thats my thought process, am i on the right track or?