In general,
with n+1 people, the number of handshakes is the sum of the
first n consecutive numbers: 1+2+3+ ... + n. Since this sum is n(n+1)/2,
we need to solve the equation n(n+1)/2 = 66. This is the quadratic
equation n2+ n -132 = 0. Solving for n, we obtain 11 as the answer and
deduce that there were 12 people at the party.
Ok so u know to divide bc u r trying to isolate the variable and that means undoing the function in this case 0.6 is multiplied to p so u do the opposite which is division
If they paid $0.72 in tax and tax is 6% or .06 then you could create an equation like this: x * .06 = .72 with x representing the original cost of the bracelet. Now you can just solve for x like so: