Answer:
b=3, y=6
Step-by-step explanation:
Label the 2 equations:
2b +6y= 42 -----(1)
2b +4y= 30 -----(2)
(1) -(2):
(2b +6y) -(2b +4y)= 42 -30
2b +6y -2b -4y= 12
2y= 12
y= 12 ÷2 <em>(</em><em>÷</em><em>2</em><em> </em><em>on</em><em> </em><em>both</em><em> </em><em>sides</em><em>)</em>
y= 6
Susbt. y=6 into (2):
2b +4(6)= 30
2b +24=30
2b= 30 -24 <em>(</em><em>-24</em><em> </em><em>on</em><em> </em><em>b</em><em>o</em><em>t</em><em>h</em><em> </em><em>sides</em><em>)</em>
2b= 6
b= 6 ÷2
b= 3
Answer:
119.05°
Step-by-step explanation:
In general, the angle is given by ...
θ = arctan(y/x)
Here, that becomes ...
θ = arctan(9/-5) ≈ 119.05°
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<em>Comment on using a calculator</em>
If you use the ATAN2( ) function of a graphing calculator or spreadsheet, it will give you the angle in the proper quadrant. If you use the arctangent function (tan⁻¹) of a typical scientific calculator, it will give you a 4th-quadrant angle when the ratio is negative. You must recognize that the desired 2nd-quadrant angle is 180° more than that.
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It may help you to consider looking at the "reference angle." In this geometry, it is the angle between the vector v and the -x axis. The coordinates tell you the lengths of the sides of the triangle vector v forms with the -x axis and a vertical line from that axis to the tip of the vector. Then the trig ratio you're interested in is ...
Tan = Opposite/Adjacent = |y|/|x|
This is the tangent of the reference angle, which will be ...
θ = arctan(|y| / |x|) = arctan(9/5) ≈ 60.95°
You can see from your diagram that the angle CCW from the +x axis will be the supplement of this value, 180° -60.95° = 119.05°.
Answer:
5n^2 - 3n - 8
Step-by-step explanation:
4n.5n - 4n.8 + 4.5n - 4.8
= 20n^2 - 32n + 20n - 32
= 20n^2 - 12n - 32
= 4 ( 5n^2 - 3n - 8 )
= 5n^2 - 3n - 8 [ answer ]
Answer:
-20,2m-11,8
Step-by-step explanation:
rewrite it
2y+14,6m+3,8-(34,8m+15,6-2y)
remove the opposites
and then simplify
-20,2m-11,8
im not sure if this makes sense
Answer:
reeeeeeeeeeeeeeeeeeeeeeeeee
Step-by-step explanation:
i dont