Step-by-step explanation:
Four bought a book at $6
4 x $6 = $24
8 x $x = $8x
Expression
$24 + $8x
Y = -(1/2)(x-2)² +8
Re write it in standard form:
(y-8) = -1/2(x-2)² ↔ (y-k) = a(x-h)²
This parabola open downward (a = -1/2 <0), with a maximum shown in vertex
The vertex is (h , k) → Vertex(2 , 8)
focus(h, k +c )
a = 1/4c → -1/2 = 1/4c → c = -1/2, hence focus(2, 8-1/2) →focus(2,15/2)
Latus rectum: y-value = 15/2
Replace in the equation y with 15/2→→15/2 = -1/2(x-2)² + 8
Or -1/2(x-2)² +8 -15/2 = 0
Solving this quadratic equation gives x' = 3 and x" = 2, then
Latus rectum = 5
Answer:
He have 43 bills of 10 and 13 bills of 5
Step-by-step explanation:
5x + 10y = 495
x + y = 56
Isolate x:
x = 56 - y
Substitute in the first equation:
5(56 - y) +10y = 495
280 -5y +10 y = 495
5y = 495 -280
5y = 215
y = 215/5
y= 43
Now substitute the value of y to find x:
x = 56 - y
x = 56 - 43
x = 13
Parallel lines have the same slope.
So the graph of [ y = 3x + any number ] is parallel
to the graph of [ y = 3x - 10 ] .