Answer:
x^2 + 5x - 84 = 0
x = 7
Step-by-step explanation:
let the sister's age = y
sister's age (y) = 5 + x equation 1
xy = 84 equation 2
Make y the subject of the formula in equation 2
y = 84/x
equate equation 1 and 2
84/x = 5 + x equation 3
Multiply equation 3 by x
84 = 5x + x^2
x^2 + 5x - 84 = 0
tjis can be solved using quadratic equation
x^2 -7x + 12x -84 = 0
x(x + 12) -7(x + 12)
x = 7 or - 12
age cant be negative so his age is 7
Answer:
69.1²feet
Step-by-step explanation:
area = pi x r²
11x2= 22
22x 3.14 = 69.08
69.1
Answer:
y = (-2/3)x + 5/6
Step-by-step explanation:
The general structure of a line in slope-intercept form is:
y = mx + b
In this form, "m" represents the slope and "b" represents the y-intercept. You have been given the value of "m". To find the value of "b", you can plug the slope and the values from the point (2, -1/2) into the general equation.
m = -2/3
Point (2, -1/2):
x = 2 and y = -1/2
y = mx + b <----- Slope-intercept form
y = (-2/3)x + b <----- Insert -2/3 in "m"
-1/2 = (-2/3)(2) + b <----- Insert "x" and "y" values from point
-1/2 = -4/3 + b <----- Multiply -2/3 and 2
-3/6 = -8/6 + b <----- Give the fractions common denominators
5/6 = b <----- Add 8/6 to both sides
Thus, the equation of the line is:
y = (-2/3)x + 5/6
Answer:
15m/s
Step-by-step explanation:
