Answer:
x = -2, y = 2
Step-by-step explanation:
-7x + 7y = 28
7y = 28 + 7x
y = 4 + x ----(1)
-8x+4y=24 -----(2)
sub (1) into (2)
-8x+4(4+x)=24
-8x+16+4x = 24
-8x+4x = 24-16
-4x = 8
x = -2
sub x = -2 into (1)
y=4+(-2) = 2
Answer: 147 Degrees
Step-by-step explanation
The size of the final unknown interior angle in a polygon is 147 degrees.
Given that,
The other interior angles are 162°, 115°, 120°, 148° and 85°.
We assume that there is an equation (2n - 4) 90.
Here n be 7.
Based on the above information, the calculation is as follows:
= (2n - 4) 90
= ((2) (7) - 4) 90
= 10 (90)
= 900
Now the size of the unknown interior angle is
= 900-(162+125+148+105+98+115)
= 900 - 753
= 147°
Therefore we can conclude that the size of the final unknown interior angle in a polygon is 147 degrees.
42 : 72 = 6 : 9
is <span>FALSE
Hope it helped : )
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Answer:
The mean of the test is 65
Step-by-step explanation:
Let the mean be x and SD be y
3 SD BELOW the mean means that we are taking away 3 SD FROM the mean
Mathematically, we have that as;
x - 3y = 41 •••••(i)
73 is 1 SD above mean
Mathematically;
x + y = 73 ••••••••(ii)
So let us solve both equations simultaneously
Simply multiply equation ii by 3 then add to i
x - 3y = 41
3x + 3y =219
4x = 41 + 219
4x = 260
x = 260/4
x = 65