Question

una recta pasa por los puntos (2;3) y (6,8) y (10;b). hallar el valor de b.

Answer 1

(2, 3)

y = ax + b
3 = a.2 + b
2a + b = 3 (-1)
-2a - b = -3

(6, 8)

y = ax + b
8 = a.6 + b
6a + b = 8

-2a - b = -3
6a + b = 8
4a = 5
a = 5/4

6a + b = 8
6.5/4 + b = 8
30/4 + b = 8
15/2 + b = 8
b = 8 - 15/2
b = 16 - 15/2
b = 1/2

y = ax + b
y = 5/4x + 1/2

(10, b)

x = 10
y = b

y = 5/4x + 1/2
y = 5.10/4 + 1/2
y = 50/4 + 1/2
y = 25/2 + 1/2
y = 26/2
y = 13
b = 13