her son mowed more. 7/20 of the lawn still needs to be mowed.
annual rate = 6 %/yr
monthly rate = ¹/₁₂ × 6 = 0.5 %/mo
if you invested $100 at 6 % annual simple interest, you would have $106 at the end of the year.
simple interest is calculated only on the principal.
if the interest were calculated at 0.5 % monthly simple interest, you would get $0.50 at the end of each month. at the end of 12 mo, you would have $106.
the ratio of the sides of triangle jkl to triangle rst is 5: 4.
let's take the corresponding sides jl and rt. note they are opposite the equal angles marked '(('.
jl / rt = 25 / 20
3x - 2y = 31
the 2-point form of the equation for a line is useful for this. for points (x1, y1) and (x2, y2), it tells you
y = (y2 -y1)/(x2 -x1)·(x -x1) +y1
substituting the given point values, we get
y = (4 ))/(13 -5)·(x -5) +(-8)
y = (12/8)(x -5) - 8 = (3/2)(x -5) -8
multiplying by 2 gives
2y = 3(x -5) -16
2y = 3x -15 -16
adding 31-2y changes this to standard form:
3x -2y = 31