Answer:
- x = 0 or 1
- x = ±i/4
- x = -5 (twice)
Step-by-step explanation:
Factoring is aided by having the equations in standard form. The first step in each case is to put the equations in that form. The zero product property tells you that a product is zero when a factor is zero. The solutions are the values of x that make the factors zero.
1. x^2 -x = 0
x(x -1) = 0 . . . . . x = 0 or 1
__
2. 16x^2 +1 = 0
This is the "difference of squares" ...
(4x)^2 - (i)^2 = 0
(4x -i)(4x +i) = 0 . . . . . x = -i/4 or i/4 (zeros are complex)
__
3. x^2 +10x +25 = 0
(x +5)(x +5) = 0 . . . . . x = -5 with multiplicity 2
<span>We use ratio and proportion to solve each of these:
</span><span>
</span><span>1.
The scale of a map is 1 in = 19.5 mi map: ________ in actual: 9.5 mi
</span><span>1 in / 19.5 mi = x in / 9.5 mi, x = 0.487 in
</span><span>
</span><span>2.
The scale of a map is 7 in = 16 mi map: 4.9 in actual: ______ mi
</span><span>7 in / 16 mi = 4.9 in / x mi, x = 11.2 mi
</span><span>
</span><span>3. The
scale factor for a model is 5 cm = ________ m Model : 72.5 cm actual:
165.3 m
</span><span>5 cm / x m = 72.5 cm / 165.3 m, x = 11.4 m
</span><span>
</span><span>4. The scale of a map is 1 in = 9.6 mi map: ________ in actual:
34.7 mi
</span><span>1 in / 9.6 mi = x in / 34.7 mi, x = 3.62 in
</span><span>
</span><span>5. The scale of a map is 1 ft = 9.6 mi map: ________ ft actual:
38.4 mi
</span><span>1 ft / 9.6 mi = x ft / 38.4 mi, x = 4 ft
</span><span>
</span><span>6. The scale factor for a model is 5 cm = ________ m Model :
22.4 cm actual: 155.2 m
</span><span>5 cm / x m = 22.4 cm / 155.2 m, x = 34.64 m
</span><span>
</span><span>7. The scale of a map is 5 in = 10 mi map: 8.7
in actual: ______ mi
</span><span>5 in / 10 mi = 8.7 in / x mi, x = 17.4 mi
</span><span>
</span><span>8. The scale of a map is 1 in = 13.5 mi map:
________ in actual: 65.9 mi
</span><span>1 in / 13.5 mi = x in / 65.9 mi, x = 4.88 in
</span><span>
</span><span>9. The scale factor for a model is 5 cm =
________ m Model : 61.5 cm actual: 143.2 m
</span><span>5 cm / x m = 61.5 / 143.2 m, x = 11.64 m
</span><span>
</span><span>10. The scale factor for a
model is 5 cm = ________ m Model : 29.7 cm actual: 179.5 m
</span><span>5 cm / x m = 29.7 cm / 179.5 m, x = 30.22 m
</span>
My work for your question
The correct answer is the Last Choice ft equals truth