Answer:
A. (9, –36)
Explanation:
The equations are given as:
i) y = -3x - 9
ii) y= 1/3 x - 39
Use equation i) in equation ii)
-3x - 9 = 1/3 x - 39 -------multiply each term by 3 to remove the fraction
-9 x - 27 = x - 117
collect like terms
-9 x- x = -117 + 27
-10 x = -90
10x = 90
x = 90 / 10
x = 9 ------------iii
Use equation iii in i
y = -3x - 9
y = -3 * 9 - 9
y= -27 - 9
y= -36
Hence,
x = 9 , y = -36