Which two numbers add up to 5 and multiply to -45 ?

We have x+y=5
xy=-45
solve
x+y=5
subtract x from both sides
y=-x+5
subsiute -x+5 for y in second equaiton
x(-x+5)=-45
-x^2+5x=-45
add 2x^2-5x to both sides
0=x^2-5x-45
use quadratic equation which is
if you have 0=ax^2+bx+c then x= or
sbsitute
1x^2-5x-45
a=1
b=-5
c=-45
subsitute




or or aprox x=-4.65891 or 9.65891, so the 2 numbers would be those answers for x

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.