Let the 1st number be x; 2nd number be y; 3rd number be z.
x + y + z = 79
x = number we are looking for.
y = x * 5 ==> 5 times the first
z = x + 16 ==> 16 more than the first
Therefor,
x + (x * 5) + (x+16) = 79
1st step, multiply the 2nd number: x * 5 = 5x
x + 5x + x + 16 = 79
Add all like numbers:
7x + 16 = 79
To get x, transfer 16 to the other side and change its sign from positive to negative.
7x = 79 - 16
7x = 63
To get x, divide both sides by 7
7x/7 = 63/7
x = 9
To check. Substitute x by 9.
x + (x * 5) + (x+16) = 79
9 + (9 * 5) + (9 + 16) = 79
9 + 45 + 25 = 79
79 = 79 equal. value of x is correct.
In general, the sum of the measures of the interior angles of a quadrilateral is 360. This is true for every quadrilateral. This does not help here, because there are two angles (angles B and D) we know nothing about. We only know about opposite angles A and C.
In this case, you can use another theorem.
Opposite angles of an inscribed quadrilateral are supplementary.
m<A + m<C = 180
3x + 6 + x + 2 = 180
4x + 8 = 180
4x = 172
x = 43
m<A = 3x + 6 = 3(43) + 6 = 135
Answer: 135 deg
Answer:
(a) 3 ft, 4 ft, 5 ft
Step-by-step explanation:
The triangle inequality requires the sum of the two short sides exceed the long side.
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a) 3 ft + 4 ft = 7 ft > 5 ft . . . . . triangle is possible
b) 4 yd + 1 2/3 yd = 5 2/3 yd < 10 yd . . . . not a possible triangle
c) 3 ft + 3 ft = 6 ft < 7 ft . . . . not a possible triangle
d) 4 in + 4 in = 8 in . . . . not a possible triangle (not greater than 8 in)
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The first set of side lengths can form a triangle: 3 ft, 4 ft, 5 ft.
Answer:
B. 4200
Step-by-step explanation:
A suitable calculator can add the terms for you. (See attached)
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The first term is 69, and the common difference is 75-69 = 6. The general term is ...
an = a1 +d(n -1)
an = 69 +6(n -1)
Then the 28th term is ...
a28 = 69 +6(27) = 231
The average term is (a28 +a1)/2 = (231 +69)/2 = 150.
The sum is the number of terms multiplied by the average term:
sum = 28×150= 4200
