It’s 3.8 inches I’m pretty sure
Answer:
Step-by-step explanation:
About 70 Cities in Total.
For his more noteworthy grandness, Alexander established exactly 70 urban areas in the grounds he vanquished and requested them named after himself. Most celebrated, obviously, is Alexandria in Egypt. In India, when his dearest horse kicked the bucket, he requested a city to be constructed named Bucephala.
Step-by-step explanation:
"identity" means an operation that does nothing.
For adding numbers, adding 0 changes nothing, so 0 is the identity for addition.
For multiplication, multiplying by 1 changes nothing, so 1 is the identity for multiplication.
There are 5 solutions for this system.
x^2 + 4y^2 = 100 ____1
4y - x^2 = -20 ____2
Add both 1 & 2 together. x^2 gets cancelled
4y^2 + 4y = 80 (send 80 to the other side and divide by 4)
Then equation the becomes : y^2 + y -20 =0
Now factorise the equation: (y+5) (y-4) = 0
Solve for y : y = -5 and y = 4
Using the values of y to find the values of x. From equation 1:
x^2 = 100 - 4y^2 x = /100 - 4y^2 (/ means square root) Replace values of y
y = -5, x = /100 - 4(-5)^2 = /100 - 100 = 0
y = 4, x = /100 - 4(4)^2 = / 100 - 64 = /36 = -6 or 6
Thus we have 6 solutions y = -5, 4 and x = -6, 0, 6
