Answer:
a). x = 11
b). m∠DMC = 39°
c). m∠MAD = 66°
d). m∠ADM = 36°
e). m∠ADC = 18°
Step-by-step explanation:
a). In the figure attached,
m∠AMC = 3x + 6
and m∠DMC = 6x - 49
Since "in-center" of a triangle is a points where the bisectors of internal angles meet.
Therefore, MC is the angle bisector of angle AMD.
and m∠AMC ≅ m∠DMC
3x + 6 = 8x - 49
8x - 3x = 49 + 6
5x = 55
x = 11
b). m∠DMC = 8x - 49
= (8 × 11) - 49
= 88 - 49
= 39°
c). m∠MAD = 2(m∠DAC)
= 2(30)°
= 60°
d). Since, m∠AMD + m∠ADM + m∠MAD = 180°
2(39)° + m∠ADM + 66° = 180°
78° + m∠ADM + 66° = 180°
m∠ADM = 180° - 144°
= 36°
e). m∠ADC = 
= 
= 18°
(9,40,41) is a Pythagorean Triple, farther down the list than teachers usually venture.
Answer: D. 41 cm
There's a subset of Pythagorean Triples where the long leg is one less than the hypotenuse,
a^2+b^2 = (b+1)^2
a^2 + b^2 = b^2 + 2b +1
a^2=2b+1
So we get one for every odd number, since the square of an odd number is odd and the square of an even number is even.
b = (a^2 - 1)/2
a=3, b=(3^2-1)/2=4, c=b+1=5
a=5, b=(5^2-1)/2 =12, c = 13
a=7, b=24, c=25
a=9, b=40, c=41
a=11, b=60, c=61
a=13, b=84, c=85
It's good to be able to recognize Pythagorean Triples when we see them.
Otherwise we'd have to work the calculator:
√(9² + 40²) = √1681 = 41
I agree with Marita, that the angles could have the same measure. This can be proven if you set the two amounts equal and solve for x.
9x - 25 + x = x + 50 + 2x - 12
To begin, we should combine like terms on both sides of the equation to start simplifying the equation.
10x - 25 = 3x + 38
Next, we should subtract 3x from both sides and add 25 to both sides to get the variable x alone on the left side of the equation.
7x = 63
Finally, we should divide both sides by 7, to get rid of the coefficient of x.
x = 9
If you plug in 9 for x in our first equation, you get that both of the angle measurements equal 65 degrees. This means that Marita is correct, because if x = 9, then the angles would have the same measure.
Answer:
There are 16 yellow houses in the neighborhood.
Step-by-step explanation:
We have that:
2/5 = 40% of the houses are painted yellow
1 - 2/5 = 3/5 = 60% of the houses are not painted yellow
If there are 24 houses that are not painted yellow, how many yellow houses are in the neighborhood?
The first step is finding the total number of houses in the neighborhood.
We have that 24 are not painted yellow, and this is 60%(0.6 decimal). How much is 100%?
We solve a rule of three
24 houses - 0.6
x houses - 1
There are 40 houses. Of those, 40% are painted yellow.
0.4*40 = 16.
There are 16 yellow houses in the neighborhood.
