If DE=52 and EF=21 Find DF

If the population of Boston, MA was 641,071 in 1970 and 574,283 in 1980 what would you expect the population to have been in 197

IRISSAK [1]

Year rank population

1790 3 18320
1800 4 24937
1810 4 33787
1820 4 43298
1830 4 61392
1840 5 93383
1850 3 136881
1860 5 177840
1870 7 250526
1880 5 362839
1890 6 448477
1900 5 560892
1910 5 670585
1920 7 748060
1930 9 781188
1940 9 770816
1950 10 801444
1960 13 697197
1970 16 641071
1980 20 562994
1990 20 574283

6 0

2 years ago

Please help me with these, oh sweet jesus

Lelechka [254]

Answer:

77. $\cot^{6} x = \cot^{4} x \csc^{2}x - \cot^{4} x$ Proved

78. $\sec^{4}x \tan^{2} x = \sec^{2}x [\tan^{2}x + \tan^{4}x ]$ Proved

79. $\cos^{3} x\sin^{2} x = [\sin^{2}x - \sin^{4}x] \cos x$ Proved.

80. $\sin^{4}x - \cos^{4}x = 1 - 2\cos^{2}x + 2 \cos^{4} x$ Proved.

Step-by-step explanation:

77. Left hand side

= $\cot^{6} x$

= $\cot^{4} x \times \cot^{2} x$

= $\cot^{4}x [\csc^{2}x - 1]$

{Since we know, $\csc^{2} x - \cot^{2}x = 1$ }

= $\cot^{4} x \csc^{2}x - \cot^{4} x$

= Right hand side (Proved)

78. Left hand side

= $\sec^{4}x \tan^{2} x$

= $\sec^{2} x [1 + \tan^{2}x] \tan^{2} x$

{Since $\sec^{2}x - \tan^{2}x = 1$ }

= $\sec^{2}x [\tan^{2}x + \tan^{4}x ]$

= Right hand side (Proved)

79. Left hand side

= $\cos^{3} x\sin^{2} x$

= $\cos x[1 - \sin^{2} x] \sin^{2} x$

{Since $\sin^{2}x + \cos^{2} x = 1$ }

= $[\sin^{2}x - \sin^{4}x] \cos x$

= Right hand side

80. Left hand side

= $\sin^{4}x - \cos^{4}x$

= $[\sin^{2}x + \cos^{2}x]^{2} - 2\sin^{2} x \cos^{2}x$

{Since $\sin^{2}x + \cos^{2} x = 1$ }

= $1 - 2\cos^{2} x[1 - \cos^{2}x ]$

= $1 - 2\cos^{2}x + 2 \cos^{4} x$

= Right hand side. (Proved)

7 0

2 years ago

What is the slope of the line in the graph?<br> 4-<br> 4 5<br><br> there is a picture ^

Ivan

Answer: x+1 is the equation and the slope will be 1/1

Step-by-step explanation:

5 0

2 years ago

What is the answer to this question?! answer quick please!

Verizon [17]

Answer:

Step-by-step explanation:

1. 8 seconds

2. 15 quarts

8 0

2 years ago

A skier is trying to decide whether or not to buy a season ski pass. A daily pass costs $65. A season pass costs $400. The skier

Vlad [161]

Let x be the number of days.

Daily pass:
65x + 30x
95x

Season pass:
400 + 30x

95x > 400 + 30x
65x > 400
x > 6.15

The number of days can't be 6.15, so you must round. You can't go down because then the price will be more expensive, so you have to round up.

It would take 7 days until the season pass is less expensive than the daily pass.
----------------------
You can check this by plugging in the x.

95x > 400 + 30x
95(7) > 400 + 30(7)
665 > 400 + 210
665 > 600
The daily pass is more expensive than the season pass.

3 0

2 years ago