Answer:
x = 4
b = 7
n = 40
I hope this helps!!!
Step-by-step explanation:
1) 12x-17 = 6x+7
+17 +17
*do this because you want to get all of the variables to one side and all of the constants to one side*
12x = 6x + 24
-6x -6x
6x = 24
*divide by 6 to get x alone, so you 24/6 = 4*
x = 4
2) -8b+1 = -5(b+4)
*must multiply -5 by everything in the parenthesises*
-8b+1 = -5b-20
-1 -1
-8b= -5b-21
+5b +5b
-3b = -21
b = 7
3) 350+10(n-7) = 630+2(n-15)
350+10n-70 = 630+2n-30
*combine like terms on both sides of the equation*
280+10n = 600+2n
-280 -280
10n = 320+2n
-2n -2n
8n = 320
n = 40
Answer:
Step-by-step explanation:
The answer is A
-25=-4r+5
Subtract 5 to each side
-25-5=-4r+5-5
-30=-4r
Divided -4 to each side
-30/-4=-4r/-4
7.5=r
Check:
-25=-4r+5
Substitute r with 7.5
-25=-4(7.5)+5
-25=-30+5
-25=-25. As a result, r=7.5. Hope it help!
Answer:
a]2.3 hrs
b]3.6hrs
Step-by-step explanation:
4hrs = 12 miles
x = 7miles
4 x 7=28/12=2.3
4 x 11=44/12=3.6hrs
Answer:
b) 105°
d) 130°
Step-by-step explanation:
An external angle has the same measure as the sum of the remote internal angles.
b) ? = 25° +80° = 105°
d) ? = 35° +95° = 130°
_____
This should be fairly obvious if you consider that the adjacent internal angle together with the external angle totals 180°, and the adjacent internal angle together with the other two internal angles totals 180°.
If the two "remote" angles are A and B, and the adjacent internal angle is C, then we have in symbols ...
A + B + C = 180° = ? + C
If we subtract C, then we find ...
A + B = ? . . . . . . the fact we used above