Question

resolva cada sistema linear.
a) [x + 2y = 6
[3x + 4y = 14

b) [7x + y = 49
[x + 4y = 61

Answer 1

a) x=6-2y
3. (6-2y) +4y= 14
18 -6y +4y =14
-6y +4y= -18 +14
-6y +4y = -4
-2y= -4. (-1)
2y= 4
y= 4÷2
y=2

b) x=49-y
x+4y=61
49-y +4.(1)= 61
-y = -49 -4 +61
-y = 8(-1)
y= -8