14. 1.5, 10 <- Answer
15. 5,1 <- Answer
Proof 14
Solve the following system:
{2 x - y = -7 | (equation 1)
4 x - y = -4 | (equation 2)
Swap equation 1 with equation 2:
{4 x - y = -4 | (equation 1)
2 x - y = -7 | (equation 2)
Subtract 1/2 × (equation 1) from equation 2:
{4 x - y = -4 | (equation 1)
0 x - y/2 = -5 | (equation 2)
Multiply equation 2 by -2:
{4 x - y = -4 | (equation 1)
0 x+y = 10 | (equation 2)
Add equation 2 to equation 1:
{4 x+0 y = 6 | (equation 1)
0 x+y = 10 | (equation 2)
Divide equation 1 by 4:
{x+0 y = 3/2 | (equation 1)
0 x+y = 10 | (equation 2)
Collect results:
Answer: {x = 1.5
y = 10
Proof 15.
Solve the following system:
{5 x + 7 y = 32 | (equation 1)
8 x + 6 y = 46 | (equation 2)
Swap equation 1 with equation 2:
{8 x + 6 y = 46 | (equation 1)
5 x + 7 y = 32 | (equation 2)
Subtract 5/8 × (equation 1) from equation 2:{8 x + 6 y = 46 | (equation 1)
0 x+(13 y)/4 = 13/4 | (equation 2)
Divide equation 1 by 2:
{4 x + 3 y = 23 | (equation 1)
0 x+(13 y)/4 = 13/4 | (equation 2)
Multiply equation 2 by 4/13:
{4 x + 3 y = 23 | (equation 1)
0 x+y = 1 | (equation 2)
Subtract 3 × (equation 2) from equation 1:
{4 x+0 y = 20 | (equation 1)
0 x+y = 1 | (equation 2)
Divide equation 1 by 4:
{x+0 y = 5 | (equation 1)
0 x+y = 1 | (equation 2)
Collect results:
Answer: {x = 5 y = 1
<h3>
Answer: 37 degrees</h3>
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Explanation:
The angle of incidence is equal to the angle of reflection. The angle of light coming in is the same as the angle of light bouncing out. Each angle is made with the dashed line as the diagram shows.
So angle RMI = 106 is bisected, i.e. divided in half, to get
- Angle RMN = 53
- Angle NMI = 53
since 106/2 = 53
Then notice that the horizontal dashed line is perpendicular to the vertical mirror. This means angle NMJ is a 90 degree angle and,
angle RMJ = (angle NMJ) - (angle RMN)
angle RMJ = 90 - 53
angle RMJ = 37 degrees
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In short: divide 106 in half to get 53, then subtract it from 90
Answer:
So x = 20
Step-by-step explanation:
AB + BC = AC sum of a segment is sum of its pieces
AB + AB = AC B is the midpoint, so AB = BC
2x + 2x = 3x + 20 putting in for AB (twice!) and AC
4x = 3x + 20 collect like terms
x = 20 subtract 3x on both sides.
Read more on Brainly.com - brainly.com/question/10838483#readmore
Answer:
Infinite
Step-by-step explanation:
3(4x + 1) - 2
= 12x + 3 - 2 (Multiply the sum in the bracket by 3)
= 12x + 1 (Simplify)
This means that:
12x + 1 = 3(4x + 1) - 2
is the same as
12x + 1 = 12x + 1
Hence, anything that is used to substitute x is correct.
