Respuesta :
Answer:
{x = -3 , y=2 (Isolved for both variables be elimination)
Step-by-step explanation:
Solve the following system:
{3 x + 5 y = 1 | (equation 1)
7 x + 4 y = -13 | (equation 2)
Swap equation 1 with equation 2:
{7 x + 4 y = -13 | (equation 1)
3 x + 5 y = 1 | (equation 2)
Subtract 3/7 × (equation 1) from equation 2:
{7 x + 4 y = -13 | (equation 1)
0 x+(23 y)/7 = 46/7 | (equation 2)
Multiply equation 2 by 7/23:
{7 x + 4 y = -13 | (equation 1)
0 x+y = 2 | (equation 2)
Subtract 4 × (equation 2) from equation 1:
{7 x+0 y = -21 | (equation 1)
0 x+y = 2 | (equation 2)
Divide equation 1 by 7:
{x+0 y = -3 | (equation 1)
0 x+y = 2 | (equation 2)
Collect results:
Answer: {x = -3 , y=2
Answer:
y = 2
Step-by-step explanation:
[tex]\left\{\begin{array}{ccc}3x+5y=1&\text{multiply both sides by 7}\\7x+4y=-13&\text{multiply both sides by (-3)}\end{array}\right\\\underline{+\left\{\begin{array}{ccc}21x+35y=7\\-21x-12y=39\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad\qquad23y=46\qquad\text{divide both sides by 23}\\.\qquad\qquad y=2[/tex]
If you want to solve it to the end, put the value of y in the first equation and solve it for x.
3x + 5(2) = 1
3x + 10 = 1 subtract 10 from both sides
3x = -9 divide both sides by 3
x = -3