The <em>echo</em> number 20222022202220222022 is the <em>perfect</em> square of 4496890281.
<h3>What echo number is a perfect square</h3>
An <em>echo</em> number has a <em>perfect</em> square if its square root is also a <em>natural</em> number. After some iterations we found that <em>echo</em> number 20222022202220222022 is a <em>perfect</em> square:

The <em>echo</em> number 20222022202220222022 is the <em>perfect</em> square of 4496890281. 
To learn more on natural numbers, we kindly invite to check this verified question: brainly.com/question/17429689
first we need to get rid of the ( ) so that we can see what the question really says
(3x³-5x² - 7+ 4x4) + (9x4 - 10x² - 5x³ + 3)
= 3x³-5x²-7+4x⁴+9x⁴-10x²-5x³+3
now all we need to do is add up the numbers with the same x's
<em>3x³</em>-5x²-7<u>+4x⁴+9x⁴</u>-10x²<em>-5x³</em>+3
= 13x⁴-2x³-15x²-4
Answer:
isosceles triangle
Step-by-step explanation:
height of pyramid = 3*(V/A)
V=48in^3
A=24in^2
So 3*(48/24) = 3*2=6
Because you have to connect the other two sides , so a diagonal line will be longer than a vertical line