Determine which postulate can be used to prove the triangles are congruent. if it is not possible to prove congruent, choose not possible.

For the the first problem that looks like a bow-tie, we don't have enough information to say if the triangles are congruent or not. We have a pair of sides and a pair of angles (the vertical angles) that are congruent, but that's about it. We can't use SSS or SAS, so that's why the answer is "not possible" for this problem.

As for the second problem, we will use SSS because we have three sets of congruent pairs of sides. The tickmarks tell us which sides pair up. The third pair of sides is the shared segment in the middle, or the diagonal of the parallelogram. We will not use SAS because we don't know anything about the angles. So we use SSS only.

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1

where's the diagram?

step-by-step explanation: