Subtract 7 from both sides
x=-4
The first one is 4*8*6=192. 4*10*3=120. 192+120=312. the answer is 312.
the second one is 9x+24. you do this by multiplying the 3 by the parenthesis and then the 2 by its parenthesis then combine variables.
First one is 15 over 32 . You have to do KEEP, CHANGE, FLIP . Keep the first fraction the same, change the division sign to a multiplication sign then flip the last fraction . 3 times 5 is 15. 8 times 4 is 32 .
Answer:
Step-by-step explanation:
1) 5(2x + 3) + 3(x -4) = 25
Use distributive property
5*2x + 5 *3 + 3*x - 3*4 = 25
10x + 15 + 3x - 12 = 25
Add like terms
10x + 3x +15 - 12 = 25
13x + 3 = 25
Subtract 3 form both sides
13x = 25 - 3
13x = 22
x = 22/13
x = 
2) Breadth = b m
Length = 5b - 4
Perimeter of rectangle = 40 m
2*(length + breadth) = 40 { Plug in the values of breadth & length}
2* (5b - 4 + b) = 40
2 * ( 6b - 4 ) = 40
2*6b - 2 *4 = 40
12b - 8 = 40 { add 8 to both sides}
12b - 8 + 8 = 40 + 8
12b = 48 { divide both sides by 12}
12b/12 = 48/12
b = 4 m
Breadth = 4m
Length = 5*4 - 4 = 20 - 4 = 16 m
If x = 1.5 is the only solution to the equation 4x² - ax + b =0 then
4x² - ax + b = 4(x - 1.5)² |use p² - 2pq + q² = (p - q)²
4x² - ax + b = 4(x² - 2x · 1.5 + 1.5²)
4x² - ax + b = 4(x² - 3x + 2.25)
4x² - ax + b = 4x² - 12x + 9 |subtract 4x² from both sides
-ax + b = -12x + 9
therefore
-a = -12 ⇒ a = 12 and b = 9