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3 years ago

Select all the equations where z=5z=5z, equals, 5 is a solution.

Mathematics

1 answer:

Serhud [2]3 years ago

8 0

Answer:

A, D and E

Step-by-step explanation:

$8 = z + 3$

Subtract 3 from both sides

$8 -3 = z + 3-3$

$5 = z$

$z = 5$

$z - 1 = 6$

Add 1 to both sides

$z - 1+1 = 6 + 1$

$z = 7$

$20 = \frac{40}{z}$

Multiply through by z

$z * 20 = \frac{40}{z} * z$

$20z = 40$

Divide through by 20

$\frac{20z}{20} = \frac{40}{20}$

$z = 2$

$12z = 60$

Divide through by 12

$z = 60/12$

$z = 5$

$12 + z = 17$

Subtract 12 from both sides

$-12 + 12 + z = 17 - 12$

$z = 5$

Hence:

A, D and E answers the question

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$SA=lw+2\cdot\dfrac{lh_1}{2}+2\cdot\dfrac{wh_2}{2}\\\\SA=lw+2\!\!\!\!\diagup\cdot\dfrac{l\cdot\frac{\sqrt{l^2+4h^2}}{2}}{2\!\!\!\!\diagup}+2\!\!\!\!\diagup\cdot\dfrac{w\cdot\frac{\sqrt{w^2+4h^2}}{2}}{2\!\!\!\!\diagup}\\\\SA=lw+\dfrac{l\sqrt{l^2+4h^2}}{2}+\dfrac{w\sqrt{w^2+4h^2}}{2}\\\\SA=\dfrac{2lw}{2}+\dfrac{l\sqrt{l^2+4h^2}}{2}+\dfrac{w\sqrt{w^2+4h^2}}{2}\\\\SA=\dfrac{2lw+l\sqrt{l^2+4h^2}+w\sqrt{w^2+4h^2}}{2}$