Question

passa pelos pontos A(3, 1) e B(-5, 4)

Answer 1

Olá Wiliam

f(x) = ax + b

f(3) = 3a + b = 1
f(-5) = -5a + b = 4

8a = -3
a = -3/8 

-9/8 + b = 8/8 
b = 17/8

f(x) = (-3x + 17)/8 

Answer 2

y=ax+b>>> 1=3a+b
y=ax+b>>> 4=-5a+b
{3a+b=1
{-5a+b=4
a=[(1.4)-(1.1)]÷[(1.(-5)-(3.1)]
a=(4-1)÷(-5-3)
a=3/-8=-3/8
b=1-3a
b=1-3.(-3/8)
b=1+9/8=17/8
y=-3x/8+17/8>>> Eq. reduzida
8y=-3x+17
3x+8y-17=0>>> Eq. geral
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