Solve the following system by substitution:

y = -1x - 5
4x - 8y = 4

x = - 3

y = - 2

Step-by-step explanation:

We have y = -1x - 5, so substitute that for y in the second equation:

4x - 8y = 4

4x - 8(-1x - 5) = 4

Now, solve for x:

4x + 8x + 40 = 4

12x + 40 = 4

12x = - 36

x = -3

Now, substitute - 3 in for x in the first equation:

y = -1x - 5 = -1(-3) - 5

y = 3 - 5

y = -2

You can check that these are right by substituting them into:

4x - 8y = 4

4(-3) - 8(-2) = 4

-12 + 16 = 4

4 = 4

So, you know that you solved correctly.

geometry: triangles

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answers archive

call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584

could you provide figure.