So the first 10 are 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. Since a prime number is only divisible by 1 and itself and greater than 1, our answers are 2, 3, 5, and 7. That's 4 numbers, or 4/10=0.4 of the 10. Since percentage is based out of 1, we can multiply 0.4 by 100 to get 40%. I hope that Helped :)
Well you are given the roots.
if we have 3 it would.have to be x^3. So something like:
y = ax^3 + bx^2 + cx + d
this could.also be written:
y = (x + a) (x + b) (x + c)
when you are able to write it like this, we know that the opposite of a, b, and c are roots. this is because if we can make any of the insides of the 3 parenthesis equal 0 then y = 0 and that x.is a root. Well if we know the 3 roots that x will be then we just have to figure out the a, b, and c. So let's plug our roots in.
y = (-1 + a) (-5 + b) (-3 + c)
now we have to make each parenthesis equal 0 to find what a, b, and c should be. It is obvious a = 1 to make.that one zero and b = 5 and c = 3. So we know a, b, and c. now let's plug.those into our first equation.
y = (x + 1) (x + 5) (x + 3)
this is your equation. You can multiply out if necessary
ok so he is owing his sister 24 and he gives her 15
so 24-15=9
but as an addition expression it will be
x+15=24
x=24-15
x=9
