Answer:
(300 + 50x)/(2 + x)
Step-by-step explanation:
Let the cost of teachers' edition books be t
Let the cost of students' edition books be s
So t = 150; s = 50
Then the total cost of 2 teachers' editions and x students' editions is 2t + sx = 2 × 150 + 50x = 300 + 50x.
The total number of books is 2 + x.
So the average cost per book is (300 + 50x)/(2 + x)
<span><span>13−<span>6x</span></span>=<span><span><span>(<span><span>2x</span>−5</span>)</span>2</span>+3</span></span>Step 1: Simplify both sides of the equation.<span><span><span>−<span>6x</span></span>+13</span>=<span><span><span>4<span>x2</span></span>−<span>20x</span></span>+28</span></span>Step 2: Subtract 4x^2-20x+28 from both sides.<span><span><span><span>−<span>6x</span></span>+13</span>−<span>(<span><span><span>4<span>x2</span></span>−<span>20x</span></span>+28</span>)</span></span>=<span><span><span><span>4<span>x2</span></span>−<span>20x</span></span>+28</span>−<span>(<span><span><span>4<span>x2</span></span>−<span>20x</span></span>+28</span>)</span></span></span><span><span><span><span>−<span>4<span>x2</span></span></span>+<span>14x</span></span>−15</span>=0</span>Step 3: Use quadratic formula with a=-4, b=14, c=-15.<span>x=<span><span><span>−b</span>±<span>√<span><span>b2</span>−<span><span>4a</span>c</span></span></span></span><span>2a</span></span></span><span>x=<span><span><span>−<span>(14)</span></span>±<span>√<span><span><span>(14)</span>2</span>−<span><span>4<span>(<span>−4</span>)</span></span><span>(<span>−15</span>)</span></span></span></span></span><span>2<span>(<span>−4</span>)</span></span></span></span><span>x=<span><span><span>−14</span>±<span>√<span>−44</span></span></span><span>−<span>8</span></span></span></span>
The answers are that the number can equal -4 or 1.
You can find this by setting the number equal to x.
x^2 (The square of a number) + 3x (three times a number) = 4
x^2 + 3x = 4 ---> subtract 4 from each side
x^2 + 3x - 4 = 0
Then you can factor this to find the answers
(x - 4)(x + 1) = 0
Set both equal to 0 and solve.
Answer:
k = +4
Step-by-step explanation:
Answer:
Jānis Čakste
Step-by-step explanation:
