Answer:
45
Step-by-step explanation:
Let the plane speed be x
Let the wind speed be y
x +y= 500.....equation 1
x -y= 410........equation 2
x + y= 500
-
x- y= 410
2x= 90
x= 90/2
x= 45
From equation 1, substitute 45 for x
x + y= 500
45 + y= 500
y = 500-45
x = 455
Hence the speed of the plane is 45
Answer:
x2+11x+28
Step-by-step explanation:
We have two binomials, so we can use the highly useful mnemonic FOIL to helps us:
Multiply the first terms:
x
⋅
x
=
x
2
Multiply the outside terms:
x
⋅
4
=
4
x
Multiply the inside terms:
7
⋅
x
=
7
x
Multiply the last terms:
7
⋅
4
=
28
Thus,
(
x
+
7
)
(
x
+
4
)
multiplies out to
x
2
+
4
x
+
7
x
+
28
, which can be simplified to:
x
2
+11
x
+
28
Hope this helps!