Answer:
45
Step-by-step explanation:
These work problems are always done in terms of fractions ie if both (Kevin & Eric) took 30mins to mow and Kevin took 1.5hrs (90mins) alone then we can make an equation like below
1/time took for both = 1/time took for Kevin + 1/time took for Eric
1/30 = 1/90+1/x ==> calling time took for Kevin x
solving the above 1/x = 1/30-1/90
1/x=2/90
x=45
Using the variable x for the unknown number,
20 - (x + 4) = 6
is your answer!
Hope I helped :)
Answer:
100
Step-by-step explanation:
well, you can just use a calculator, or your mind if that's possible, to solve this.
at least, what i think you're asking.
400 × 0.25 = 100.
this one is extra easy because you should know that 25% is a quarter, and 400 can just be divided by 4 to get your answer.
Answer:

Step-by-step explanation:
The equation of a line is usually written in the form of y=mx+c, where m is its gradient and c is its y-intercept.
First rewrite the equation of the given line in the form of y=mx +c.
4x+5y=25
5y= -4x +25

The gradient of the given line is 
The product of the gradient of perpendicular lines is -1.

Thus, m= 

Substitute a coordinate to find c.
When x= -4, y= -6,

Hence, the equation of the line is
