Answer:
See below.
Step-by-step explanation:
ABC is an isosceles triangle with BA = BC.
That makes angles A and C congruent.
ABD is an isosceles triangle with AB = AD.
That makes angles ABD and ADB congruent.
Since m<ABD = 72 deg, then m<ADB = 72 deg.
Angles ADB and CDB are a linear pair which makes them supplementary.
m<ADB + m<BDC = 180 deg
72 deg + m<BDC = 180 deg
m<CDB = 108 deg
In triangle ABD, the sum of the measures of the angles is 180 deg.
m<A + m<ADB + m<ABD = 180 deg
m<A + 72 deg + 72 deg = 180 deg
m<A = 36 deg
m<C = 36 deg
In triangle BCD, the sum of the measures of the angles is 180 deg.
m<CBD + m<C + m<BDC = 180 deg
m<CBD + 36 deg + 108 deg = 180 deg
m<CBD = 36 deg
In triangle CBD, angles C and CBD measure 36 deg making them congruent.
Opposite sides DB and DC are congruent making triangle BCD isosceles.
Answer:
difference between linear equations and inequalities is the solution set. A linear equation of two variables can have more than one solution. For instance, with x = 2_y_ + 3, (5, 1), then (3, 0) and (1, -1)
Step-by-step explanation:
Answer:
-52/75
Step-by-step explanation:
Answer:
x = 16
Step-by-step explanation:
The equation shown can be solved this way.
x^2 +(x -4)^2 = 20^2
x^2 +x^2 -8x +16 = 400
2x^2 -8x -384 = 0
x^2 -4x -192 = 0
(x -16)(x +12) = 0
The positive solution is ...
x = 16
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Since this makes use of the Pythagorean theorem, you've probably run across the 3-4-5 triangle. You often find scaled versions of it in algebra and geometry problems. Here, it is scaled by a factor of 4 to give a 12-16-20 triangle as half of the display screen.
The 3-4-5 triple is the only Pythagorean triple that is an arithmetic sequence. So, if the difference in side lengths is 4 and the diagonal is 5×4, you can be pretty certain that x = 4×4 and x-4 = 4×3.
Х - 15 = 32
х = 32 + 15
x = 47 (answer)
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47 - 15 = 32
32 = 32
х - 7.2 = 23,1
х = 23,1 + 7.2
х = 30,3 (answer)
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30,3 - 7,2 = 23,1
23,1 = 23,1
