Answer:
6 years
Step-by-step explanation:
So each person's age can be represented as a linear equation, since each year our age increases by 1. It can be represented in the slope-intercept form: y=mx+b. The slope in this case is going to be 1, since the time is going to be years, and each year everyone's age goes up by 1 (of course if you're still alive...) and y-intercept in this case represents their current age.
So the father can be represented as: y=x+38
The sons can be represented as: y = x+13 and y=x+5
The daughter can be represented as: y=x+8
So adding up all his children you get:
(x+13)+(x+5)+(x+8)
This gives you the equation:
3x+26
Now set this equal to the father's age to solve for x (in this context it's years)
3x+26=x+38
Subtract from both sides
2x+26=38
Subtract 26 from both sides
2x=12
Divide both sides by 2
x=6
So in 6 years the father will be the same age as his children put together
2/1 = 14/x
cross mulitply
2x=14
2x/2=14/2
x=7
The width is 7 cm
Answer:
Both answers will give an area of 2400 ft2
but with x=60 we have lawn dimensions -60 ft by -40 ft so this is out
x = 10 ft width for the sidewalk
Check: New lawn dimensions
(80-2x)(60-2x) = 60(40) = 2400 ft^2
Step-by-step explanation:
Draw a diagram:
We have a rectangle inside a rectangle.
The larger outside rectangle is the original lawn: 80ft by 60 ft with area 4800 ft2
The smaller inside rectangle is (80-2x)by(60-2x) where x is width of the new sidewalk.
Area of new lawn is 2400 ft^2
(80-2x)(60-2x) = 2400
4800 - 160x - 120x + 4x2 = 2400
4x2 - 280x + 2400 = 0
Factor out a 4
x2 - 70x + 600 = 0
(x-60)(x-10) = 0
x = 60 ft or x = 10 ft
The answer is D (-2, 1), (0, -1), (2, -3)
Answer:
135 is the amount of that she has for now
