Answer:
(0,3) is the solution set for given system.
Step-by-step explanation:
Given that:
3x+4y=12 ------- eq1
2x-3y= -9 ------- eq2
Multiplying eq1 with 2 and eq2 with 3 we get:
6x + 8y = 24 --------- eq1
6x - 9y = -27 -------- eq2
Subtracting eq2 from 1 we get:
17y = 51
Dividing both sides by 17 we get:
y = 3
Putting value of 3 in eq1 we get:
3x + 4(3) = 12
3x + 12 = 12
3x = 0
Dividing both sides by 3
x = 0
So the solution set will be: (0,3)
i hope it will help you.
Multiply the top one by 3 for x, so you can eliminate x and find y
then plug in the y into one of the equations to find x
Answer:
I really don't know, sorry I cant help
Because x,y,z form a geometric sequence, therefore the common ratio is
r = y/x = z/y
That is,
y² = xz (1)
We are given:
x + y + z = 18
Therefore
x + z = 18 - y (2)
Also,
x² + y² + z² = 612
Therefore, from (1), obtain
x² + z² + xz = 612
(x + z)² - xz = 612
From (1) and (2), obtain
(18 - y)² - y² = 612
324 - 36y + y² - y² = 612
-36y = 288
y = -8
Answer: y = -8