Question

Dado os pares ordenados Seguinte,determine a lei de formação do 1° grau.
A) A(2,-6) e B(5,0)
B) A(7,9) e B(-2,-5)
C) A(-3,5) e B(2,-4)
D) A(1,-12) e B (15,7)
Alg me ajuda pfv

Answer 1

A) A(2,-6) e B(5,0)

y=ax+b

-6=2a+b  (i)

0=5a+b (ii)

(i)-(ii)

-6=-3a  ==>a=2

0=5a+b ==>b=-5a=-10

y=2x-10

 B) A(7,9) e B(-2,-5)

y=ax+b

9=7a+b (i)

-5=-2a+b (ii)

(i)-(ii)

14=9a ==>a=14/9

-5=-2a+b ==>-5=-28/9 + b ==>-45=-28 +9b ==> b=-17/9

y=(14x-17)/9

 C) A(-3,5) e B(2,-4)

y=ax+b

5=-3a+b  (i)

-4=2a+b (ii)

(i)-(ii)

9=-a ==>a=-9

5=-3x+b ==>5=27+b==> b=-22

y=-9x   -22

D) A(1,-12) e B (15,7)

y=ax+b

-12=-a+b  (i)

7=15a+b (ii)

(i)-(ii)

-19 =-16a  ==>a=-19/16

-12=-a+b ==>-12=-19/16 +b ==>b=-173/16

y=-19x/16-173/16