Answer:
y = -3
x = 
Step-by-step explanation:
4(y +
) - 2y = 8 Distribute the 4. Multiply everything in the parentheses by 4
4y + 14 - 2y = 8 4
=
= 14 Combine the like terms 4y and -2y
2y + 14 = 8 Subtract 14 from both sides
2y = -6 Divide both sides by 2
y = -3
Plug -3 in for y in either original equation.
4x - 2y = 8
4x -2(-3) = 8
4x + 6 = 8 Subtract 6 from both sides
4x = 2 Divide both sides by 4
x =
= 
Check:
x = y + 
= -3+ 
=
+ 
= 
4x - 2y = 8
4(
) - 2(-3) = 8
2 + 6 = 8
8 = 8
Answer:
6cm ; 22cm
Step-by-step explanation:
Given that:
Total Length, AD = 28cm
AB =x cm
BC = (x +5)cm
CD = 2x - 1 cm
4x + 4 = 28
4x = 28 - 4
4x = 24
x = 24 / 4
x = 6cm
The length of BD
BD = BC + CD
BD = (x + 5) + (2x - 1)
x = 6
BD = (6 + 5) + (2(6) - 1)
BD = 11 + (12 - 1)
BD = 11 + 11
BD = 22 cm
Answer:B
Step-by-step explanation:
Answer:
The square roots of 400 are 20 and -20.
Step-by-step explanation:
You can try the offered answers to see if they square to give 400:
(-40)² = 1600 . . . . -40 is not a square root of 400
(-20)² = 400 . . . . -20 is a square root of 400
20² = 400 . . . . . 20 is a square root of 400
40² = 1600 . . . . 40 is not a square root of 400
_____
The second degree equation ...
x² = 400
will have exactly two solutions, as required by the fundamental theorem of algebra. Those solutions are both given above. There are no other square roots of 400, real or complex.