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What are 2 numbers that add to 16 and multiply to 10

1 Answer

5 votes
find multipules of 10
1 and 10
2 and 5
1+10=11 NO
2+5=7 ono

so do
x+y=16
xy=10

x+y=16
subtract x from both sides
y=16-x
subsitute
x(16-x)=10
distribute
16x-x^2=10
add x^2 to btoh sides
16x=x^2+10
subtrac 16 x from oth sies
0=x^2-16x+10
use quadratic formula which is
x=
\frac{-b+/- \sqrt{ b^(2)-4ac } }{2a} when you have
0=ax^2+bx+c

0=x^2-16+10
a=1
b=-16
c=10
subsitute
x=
\frac{-(-16)+/- \sqrt{ (-16)^(2)-4(1)(10) } }{2(1)}
x=
(16+/- √( 256-40 ) )/(2)
x=
(16+/- √( 216 ) )/(2)
x=
(16+/- 6√(6 ) )/(2)
x=
8+/- 3√(6)
x=8+
3 √(6) or 8-
3 √(6)
aprox
x=15.3485 or 0.651531
so thos are the 2 numbers


User Udi Cohen
by
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