Answer: x = -1, -3, 7 + √62, 7 - √62
Step-by-step explanation:
q p
x⁴ - 10x³ - 66x² - 94x - 39
= +/- 
possible rational factors: 1, -1, 3, -3, 13, -13, 39, -39
Use synthetic division <em>or long division</em> to see which factor will leave a remainder of 0.
try x + 1 = 0 ⇒ x = -1
-1 | 1 -10 -66 -94 -39
<u>| ↓ -1 11 55 39 </u>
1 -11 -55 -39 0
(x + 1)(x³ - 11x² - 55x - 39)
next, try x + 3 = 0 ⇒ x = -3 <em>for the new polynomial</em>
-3 | 1 -11 -55 -39
<u>| ↓ -3 42 39</u>
1 -14 -13 0
(x + 1)(x + 3)(x² - 14x - 13)
Lastly: find the zeros by setting each factor equal to zero and solve.
x + 1 = 0 ⇒ x = -1
x + 3 = 0 ⇒ x = -3
x² - 14x - 13 = 0
Answer : The number is 4.
Step-by-step explanation:
<u>Given : </u>
six times a number, increased by 3 is is 27.
<u>To Find: </u>
The number.
<u>Solution : </u>
Let the number is x
six times a number is 6x
Increased by 3 = 6x+3
According to the given question :
<u>Solving the value x : </u>
6x+3 =27
6x = 27-3
6x = 24
x = 24/6
x = 4
Hence, the number is 4.
Answer:
(4,-6)
Step-by-step explanation:
Let x be the number of pounds of the $1.35 beans. The cost of those beans is $1.35 * x, or 1.35x.
<span>Let y be the number of pounds of the $1.05 beans. The cost of those beans is $1.05 * y, or 1.05y. </span>
<span>We know that 120 pounds of the mix sells for $1.15/pound, for a total of 120 * 1.15 = $138. </span>
<span>x + y = 120 </span>
<span>1.35(x) + (1.05)y = 138 </span>
<span>We can rewrite the first as </span>
<span>x = -y + 120 </span>
<span>Now we can substitute (-y + 120) in for (x) in the second equation, because we just proved they're equal. </span>
<span>1.35(x) + 1.05(y) = 138 </span>
<span>1.35(-y + 120) + 1.05y = 138 </span>
<span>-1.35y + 162 + 1.05y = 138 </span>
<span>-0.3y + 162 = 138 </span>
<span>-0.3y = -24 </span>
<span>y = 80 </span>
<span>And since x + y = 120, that means x = 40. </span>
<span>Check: </span>
<span>40 pounds of x at $1.35 costs 40 * 1.35, or $54. </span>
<span>80 pounds of y at $1.05 costs 80 * 1.05, or $84. </span>
<span>Do those add up to our target total, according to the question, of 120 * 1.15 = $138? </span>
