Let the smaller number be x and the larger number be y.
We can calculate this by using simultaneous equation, aka listing 2 equations out.
From given,
X + y = 43
Let this be equation no. 1
X + 19 = y
Let this number be equation 2.
We can do simultaneous equations either by substitute method or elimination. In this case I'm using substitute.
We can already obtain the value of y (in terms of x) in euqation no. 2, so all we gonna do is to put y into equation 1.
X + x + 19 = 43
Solve this by algebra.
2x = 43 - 19
X = 12
Now we know the exact value of x
Now substitute x = 12 into equation no. 2
12 + 19 = y
Y = 31
So the answer is 12 and 31
The sum of the first 20 terms of an arithmetic sequence with the 18th term of 8.1 and a common difference of 0.25 is 124.5
Given,
18th term of an arithmetic sequence = 8.1
Common difference = d = 0.25.
<h3>What is an arithmetic sequence?</h3>
The sequence in which the difference between the consecutive term is constant.
The nth term is denoted by:
a_n = a + ( n - 1 ) d
The sum of an arithmetic sequence:
S_n = n/2 [ 2a + ( n - 1 ) d ]
Find the 18th term of the sequence.
18th term = 8.1
d = 0.25
8.1 = a + ( 18 - 1 ) 0.25
8.1 = a + 17 x 0.25
8.1 = a + 4.25
a = 8.1 - 4.25
a = 3.85
Find the sum of 20 terms.
S_20 = 20 / 2 [ 2 x 3.85 + ( 20 - 1 ) 0.25 ]
= 10 [ 7.7 + 19 x 0.25 ]
= 10 [ 7.7 + 4.75 ]
= 10 x 12.45
= 124.5
Thus the sum of the first 20 terms of an arithmetic sequence with the 18th term of 8.1 and a common difference of 0.25 is 124.5
Learn more about arithmetic sequence here:
brainly.com/question/25749583
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Answer:
h = 5.318 m
Step-by-step explanation:
6.5/11 = h/9
0.5909 = h/9
h = 5.318
Answer:
b=19
Step-by-step explanation:
2x(3x+5)+3(3x+5)=ax2 +bx+c
by expansion,
6x2 +10x +9x+15=6x2 +19x +15
