Step-by-step explanation:
a.
simply add both equations
x + y = 2
-3x - y = 5
----------------
-2x + 0 = 7
x = -7/2
x + y = 2
-7/2 + y = 2
y = 2 + 7/2 = 4/2 + 7/2 = 11/2
b.
1/2 x + 2y = -13
x - 4y = 8
first multiply the first equating by 2
x + 4y = -26
x - 4y = 8
--------------------
2x + 0 = -18
x = -18/2 = -9
x - 4y = 8
-9 - 4y = 8
-4y = 17
y = -17/4
1-2m-5m=15
combine like terms
1 -7m = 15
subtract 1 from each side
1-1-7m = 15-1
simplify
-7m = 14
divide by -7
-7m/-7 = 14/-7
simplify
m = -2
Answer:
x=2/3
Step-by-step explanation:
(2x+1)/2 = 2 1/3/4
Multiply 4 on both sides:
2x+1=2 1/3
Rewrite:
2x+1=7/3
Subtract 1 on both sides:
2x=4/3
Divide 2 on both sides:
x=2/3
Thus x=2/3
Hope this helps!
<h3>
Answer: 12.5 (choice C)</h3>
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We apply the pythagorean theorem to find this answer.
a = 11 and b = 6 are the given legs
c = unknown hypotenuse
So,
a^2+b^2 = c^2
c = sqrt( a^2+b^2 )
c = sqrt( 11^2 + 6^2 )
c = sqrt( 121 + 36 )
c = sqrt( 157 )
c = 12.52996 approximately
c = 12.5
Side note: once you replace 'a' and b with 11 and 6, you can compute everything with a calculator in one single step more or less. The steps above are shown if you wanted to find the exact value sqrt(157).
You can divide a triangle using medians. Let's name triangle ΔABC shown in figure 1. So you must start at one of the vertices and then bisect the opposite side. Let's start with the point A and then we bisect the opposite side. Then the length from B to D is equal to the length from D to C. So let's take the point B and then we bisect the opposite side. Then the length from A to E is equal to the length from E to C. The same reasoning happens with the point C. So we have, in figure 2, the triangle ΔABC divided into six triangles which all have the same area.
