Respuesta :
Answer:
x = 2/3 , y = -23/12
Step-by-step explanation:
Solve the following system:
{-7.5 x - 1.2 y = -2.7
{1.2 y - 1.5 x = -3.3
In the first equation, look to solve for x:
{-7.5 x - 1.2 y = -2.7
{1.2 y - 1.5 x = -3.3
-7.5 x - 1.2 y = -(15 x)/2 - (6 y)/5 and -2.7 = -27/10:
{-(15 x)/2 - (6 y)/5 = -27/10
Add (6 y)/5 to both sides:
{-(15 x)/2 = 3/10 (4 y - 9)
{1.2 y - 1.5 x = -3.3
Multiply both sides by -2/15:
{x = 1/25 (9 - 4 y)
{1.2 y - 1.5 x = -3.3
Substitute x = 1/25 (9 - 4 y) into the second equation:
{x = 1/25 (9 - 4 y)
{1.2 y - 0.06 (9 - 4 y) = -3.3
1.2 y - 0.06 (9 - 4 y) = 1.2 y + (0.24 y - 0.54) = 1.44 y - 0.54:
{x = 1/25 (9 - 4 y)
{1.44 y - 0.54 = -3.3
In the second equation, look to solve for y:
{x = 1/25 (9 - 4 y)
{1.44 y - 0.54 = -3.3
1.44 y - 0.54 = (36 y)/25 - 27/50 and -3.3 = -33/10:
(36 y)/25 - 27/50 = -33/10
Add 27/50 to both sides:
{x = 1/25 (9 - 4 y)
{(36 y)/25 = -69/25
Multiply both sides by 25/36:
{x = 1/25 (9 - 4 y)
{y = -23/12
Substitute y = -23/12 into the first equation:
Answer: x = 2/3 , y = -23/12
Answer:
x = 2/3 y = -23/12
Step-by-step explanation:
- 7.5x - 1.2y = -2.7
- 1.5x + 1.2y = -3.3
Add the equations together
- 7.5x - 1.2y = -2.7
- 1.5x + 1.2y = -3.3
---------------------------
-9x = -6
Divide each side by -9
-9x/-9 =-6/-9
x =2/3
Now we need to find y
-1.5 (2/3) +1.2y = -3.3
-1 +1.2y = -3.3
Add 1 to each side
-1+1 +1.2y = -3.3+1
1.2y = -2.3
Divide by 1.2
1.2y/1.2 = -2.3/1.2
y =-23/12