Answer: Robert's present age is 10 years
Robert father's present age is 40 years
Step-by-step explanation:
Let r = Robert's current age
Let y = Robert father's current age
Robert's father is 4 times as old as robert. This means that
y = 4x
After 5 years, Robert's father will be three times as old as Robert. This means that
y + 5 = 3(x+5)
y + 5 = 3x + 15 - - - - - - - ;1
We will substitute y = 4x into equation 1. It becomes
4x + 5 = 3x + 15
Collecting like terms,
4x - 3x = 15 - 5
x = 10
y = 4x
Substituting x = 10,
y = 4× 10 = 40 years
Answer:
(x - 2)² + (y + 7)² = 64
(fourth option listed / option D)
Step-by-step explanation:
as you likely know, the equation of a circle (centered at origin) is x²+y²=r²
now, let's say we want to write this using the center (the origin), it could look like this:
(x - 0)² + (y - 0)² = r²
(the center is 0,0)
[we write this in parentheses when we are shifting the location of a point--similar to when we move a line on a graph]
We can use this for any center, and we write our circle equation as:
(x - h)² + (y - k)² = r²
(h, k) is the center
So, let's apply the information we know
our (h, k) is (2, -7)
so let's fill that in:
(x - h)² + (y - k)² = r²
(x - 2)² + (y - -7)² = r² (simplify)
(x - 2)² + (y + 7)² = r²
now, we also know that our "r" <em>(r is the radius)</em> is 8, so let's fill that in too:
(x - 2)² + (y + 7)² = r²
(x - 2)² + (y + 7)² = 8² (simplify)
(x - 2)² + (y + 7)² = 64
So, we have found the equation of our circle to be:
(x - 2)² + (y + 7)² = 64
hope this helps! (and hope this makes sense) have a lovely day :)
Answer:
67
Step-by-step explanation:
To round 67.498 to the nearest whole number consider the tenths’ value of 67.498, which is 4 and less than 5. Therefore, we have to round down: the whole number ones place value of 67.498, 67, remains 67, and the decimal point and all digits (.498) are removed.
67.498 rounded to the nearest whole number = 67
2 hours=160
1 hours=160÷2=80
30 minutes=80÷2=40
Answer:She can paste 40 stamps in 30 minutes
Answer:
Width=4, and Length=17
Step-by-step explanation:
first you will make a variable for the width which i will say is x
now make it an equation (3x+5) (x) = 68
then solve 3x^2+5x=68
then 3x^2+5x-68=0
then x=4
then you have to substitute so 3(4)+5= 17 and 4