Three positive numbers are in arithmetic progression (a. p). the sum of the squares of the three numbers is 155. while the sum of the numbers is 21. if the common difference is positive. find the values of x and y

The required arithmetic sequence will be 5, 7, and 9 if the sum of the squares of the three numbers is 155. while the sum of the numbers is 21

Let the three positive numbers be a-d, a and a + d

If the sum of the numbers is 21, this means that a-d+a+a+d = 21

3a -d + d = 21

3a = 21

a = 21/3

a = 7

The sequence of numbers will be 7-d, 7 and 7+d

If the squares of the three numbers is 155, hence;

Hence the required arithmetic sequence will be 5, 7 and 9

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step-by-step explanation:

given that there are two triangles j'k'l' and jkl>

the former is got by dilating the second one.

when drawn on a grid, (graph paper) coordinates of vertices of first triangle is

(6,12)j, (9,6)k and (12,9)l

side jk has length = distance between j and k

=

side j'k'=distance between j' and k'

=

ie j'k'l' has sides 1/3 of that of corresponding sides of jkl.

hence scale factor of 1/3 is used to get j'k'l'from jkl

your answer is -9

step-by-step explanation: