Ola Jose

pontos

A(2,5)

B(-1,6)

R(x,0) (raiz)

2 5 1

-1 6 1

x 0 1

2 5 1

-1 6 1

det = 12 + 0 + 5x - 6x - 0 + 5 = 0

x = 17

pronto

m = (6 - 5)/(-1 - 2)

m = 1/(-3)

m = -1/3

2m + b = 5

-2/3 + b = 5

b = 5 + 2/3

b = 17/3

-x/3 + 17/3 = 0

-x/3 = -17/3

-x = -17

x = 17

y=ax+b

(2, 5) ==>5=2a+b (i)

(-1, 6) ==>6=-a+b (ii)

(i)+2(ii)

17=3b ==>b=17/3

6=-a+17/3

a=17/3-6

a=-1/3