Question

if x = 3z + 4; y = x - 4 and z =1.5 , find the value of 2x + 3y - 2z ?

(1) 33.5
(2) 27.5
(3) 6.5
(4)7.5
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Answer 1

Given

x= 3z + 4; y = x - 4 and z =1.5

i)x=3×1.5 +4

= 4.5+4

= 8.5

ii ) y = x - 4

= 8.5 - 4

= 4.5

Now,

2x+3y-2z

=2×8.5 +3×4.5-2×1.5

= 17+13.5-3

= 30.5 - 3

= 27.5

Option (2) is correct.

••••

Answer 2

$\huge\red{\mathfrak{Heyaa\:Mate}}$

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$\huge{\mathfrak{Solution}}$

$2x + 3y - 2z \\ x = 3z + 4 \\ = > 3(1.5) + 4 \\ = > 4.5 + 4 \\ = > 8.5$

$z = 1.5$

$by \: inserting \: the \: value \: \\ of \: x \: y \: and \: z$

$y = > x - 4 \\ = > 8.5 - 4 \\ = > 4.5$

$= > 2(8.5) + 3(4.5) - 2( 1.5)$

$= > 17 + 13.5 - 3 \\ = > 30.5 - 3 \\ = > 27.5$

$\huge\mathbb\red{\mid{\underline{\overline{B)\:27.5}}}\mid}$

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THANKS♥