The equation representing when the two planes would be at the same altitude is 9x=486
<h3>In terms of mathematics, what is an equation?</h3>
Equation: A declaration that two expressions with variables or integers are equal. In essence, equations are questions, and attempts to systematically identify the solutions to these questions have been the driving forces behind the creation of mathematics.
From (a) we get that: Altitude of Plane A = 990-18x
Altitude of Plane B = 1476-27x
make 890 - 18x = 1476-27x
-18x+27 x = 1476-890
9x=486
X= 54
so pass 54 seconds will the two plane at the same altitude.
To learn more about equations from given link
brainly.com/question/25678139
#SPJ9
You can answer this problem in two different ways: the first being (17 - 5) * x, and the second being 12 * x.
To simplify 7C4 we use the combination formula given by:
nCr=n!/[(n-r)!r!]
thus:
In our case we shall have:
n=7 and r=4
7C4
=7!/[(7-4)!4!]
=5040/[6×24]
=5040/144
=35
The answer is 35
