<span>Simplifying
x + -1.4 = 7.82
Reorder the terms:
-1.4 + x = 7.82
Solving
-1.4 + x = 7.82
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '1.4' to each side of the equation.
-1.4 + 1.4 + x = 7.82 + 1.4
Combine like terms: -1.4 + 1.4 = 0.0
0.0 + x = 7.82 + 1.4
x = 7.82 + 1.4
Combine like terms: 7.82 + 1.4 = 9.22
x = 9.22
Simplifying
x = 9.22</span>
Length of train : 100
length of bridge : 400
distance covered by the train to cross the bridge : (100 + 400) = 500
time taken by the train to cross : 30
speed = distance / time
speed = 500/30
speed = 16.67 meters per second <===
Let x be the number you want to find
435= x times 25 times 3
435= 75x
X= 435/75 =5.8 (ans)
<h2><em>y
2
+
6
y
−
16
=
(
y
+
8
)
(
y
−
2
)
</em></h2><h2 /><h2><em>Explanation:
</em></h2><h2><em>Note that in general:
</em></h2><h2 /><h2><em>(
y
+
a
)
(y
−
b
)
=
y
2
+
(
a
−
b
)
y
−
a
b
</em></h2><h2 /><h2><em>So we want to find a pair of factors a and b of 16 which differ by 6
. </em></h2><h2><em>The pair 8
,
2 works in that 8−
2
=
6 and 8
⋅
2=
16
.
</em></h2><h2 /><h2><em>Hence:
</em></h2><h2><em>
y
2
+
6
y
−
16
=
(
y+
8
)
(
y
−
2
)</em></h2><h2><em>y=2,-8</em></h2>
