Answer:
x=8, y = 0
Step-by-step explanation:
Substitution is easier for this problem.
3x + y = 24 ---> y = 24 - 3x
x^2 + y = 64
Substitute y
x^2 + 24 - 3x = 64
x^2 - 3x = 40
Factor out x
x(x-3) = 40
Pretty much you can guess and check
x = 8
If x = 8, y = 0
or
x^2 - 3x = 40
Complete the square
x^2 - 3x + 2.25 = 42.25
(x-1.5) ^2 = 42.25
Square root both sides
x - 1.5 = 6.5
x=8
x - 1.5 = -6.5
x = -5
Check
x = -5 doesn't work, so x = 8 and y = 0
( 4.625, - 3.75 )
the midpoint of (x₁, y₁ ) and (x₂, y₂ ) is
[
(x₁ + x₂ ), (y₁ + y₂ ) ]
here (x₁, y₁ ) = (5.5, - 4.75 ) and (x₂, y₂ ) = (3.75, - 2.75 )
[ (5.5 + 3.75 ), (- 4.75 - 2.75 ) ]
= (4.625, - 3.75 ) ← midpoint of HX
Answer:
there are 25 students in the class and 15 who wear glasses.
