Answer:
x=3
Step-by-step explanation:
Step 1: Simplify both sides of the equation.
2(x−5)+8=4
(2)(x)+(2)(−5)+8=4(Distribute)
2x+−10+8=4
(2x)+(−10+8)=4(Combine Like Terms)
2x+−2=4
2x−2=4
Step 2: Add 2 to both sides.
2x−2+2=4+2
2x=6
Step 3: Divide both sides by 2.
2x/2 = 6/2
x=3
Answer: 90%
Step-by-step explanation:
54/60=0.9 0.9*100= 90
<u>Question 8</u>
a^2 + 7a + 12
= (a+3)(a+4)
When factorising a quadratic, the product of the two factors should equal the constant term (12), and the sum of the two factors should equal the linear term (7). To find the two factors, list out the factors of 12 (1x12, 2x6, 3x4) and identify the pair that adds up to 7 (3+4).
An alternative method if you get stuck during your exam would be to solve it algebraically using the quadratic formula and then write it in the factorised form.
a = (-7 +or- sqrt(7^2 - 4(1)(12)) / 2(1)
= (-7 +or- sqrt(1))/2
= -3 or -4
These factors are the negative of the values that would go in the brackets when written in factorised form, as when a = -3 the factor (a+3) would equal 0. (If it were positive 3 instead, then in the factorised form it would be a-3).
<u>Question 10</u>
-3(x - y)/9 + (4x - 7y)/2 - (x + y)/18
Rewrite each fraction with a common denominator so you can combine the fractions into one.
= -6(x - y)/18 + 9(4x - 7y)/18 - (x + y)/18
= (-6(x - y) + 9(4x - 7y) - (x + y)) /18
Expand the brackets and collect like terms.
= (-6x + 6y + 36x - 63y - x - y)/18
= (29x - 58y)/18
= 29/18 x - 29/9 y
I believe it’s 1.5558 x 10 to the 4th power
9514 1404 393
Answer:
x = 16
Step-by-step explanation:
Either or both of the right triangles can be used to find x. Or, triangle ABC could be used. All numbers are assumed to be degrees.
<u>Using ∆ABD</u>
55 +90 +2x+3 = 180
2x = 32 . . . . . . subtract 148
x = 16
<u>Using ∆BCD</u>
50 +90 +2x+8 = 180
2x = 32 . . . . . . subtract 148
x = 16
<u>Using ∆ABC</u>
55 +(2x +3) +50 +(2x +8) = 180
4x = 64 . . . . . . . subtract 116
x = 16
