Answer:
Step-by-step explanation:
Find the slope and then the equation of line.
(x₁ , y₁) = (2 , 2) & (x₂, y₂) = (6 , 10)
m = 2
Equation of the line: y - y₁ = m(x - x₁)
y - 2 = 2 (x - 2)
y - 2 = 2x - 4
y = 2x - 4 + 2
y = 2x - 2 --------------(I)
(a, 8)
Plug in x = a & y = 8 in (I)
8 = 2a - 2
8 + 2 = 2a
10 = 2a
a = 10/2
a = 5
(4 , b)
Plug in x = 4 & y = b in (I)
b = 2*4 - 2
b = 8 - 2
b = 6
A multiplication is zero if and only if at least one of the factors is zero. So, in this case, the multipications equals zero when
The first equation has no real solutions, because is a square, and thus it's positive. If you add 4 to a positive number, the result can't be zero.
The second equation has the solution
So, globally, the expression equals zero if and only if