Answer:
20. 4n+5+8n-5=180(linear pair)
12n=180
n=15
21. 9x-6=8.5x+2(can be seen from image)
9x-8.5x=2+6
0.5x=8
x=8/0.5
x=80/5
x=16
22. 4z+3z+6=90°(Complementary)
7z+6=90°
7z=84°
z=12°
Try breaking these into sections.
Twice: 2 times
The sum of: add
A number: choose a variable, like x
---Thus "the sum of a number and 4" becomes "add x and 4" which, mathematically, is "x+4"
-----Continuing to put it all together, "Twice the sum of a number and four" becomes "2 times (x+4)" which, mathematically, is "2(x+4)"
Is: equals
-------"Twice the sum of a number and four is" becomes "2(x+4)="
23 less than: subtract 23. This one tends to trick people; "23 less than" will become "__ - 23", NOT "23 - __"
three times the number: 3 times x
---"23 less than three times the number" becomes "subtract 23 from 3 times x" which, mathematically, is "3x-23"
-------So the final phrase: 2(x+4)=3x-23"
Answer:4 times x
4(x)
Step-by-step explanation:
4 times as many songs on Lou's music player
Lou's music player is x
Answer:
b and c
Step-by-step explanation:
You would multiply it by 4
4(3x^2 +2 )
12x^2 +8
